Ebook Averys diseases of the newborn (10th edition): Part 3

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Part 3 book "Averys diseases of the newborn" includes content: Abdominal wall defects, gastrointestinal tract development, structural anomalies of the gastrointestinal tract, innate and mucosal immunity in the developing gastrointestinal tract, neonatal gastroesophageal reflux, the intestinal microbiome, necrotizing enterocolitis and short bowel syndrome,... and other contents.

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PA RT XIII Nutrition 67 Breastfeeding LYDIA FURMAN AND RICHARD J. SCHANLER KEY POINTS Rates of Breastfeeding in the United States • Hospital policies must support mothers who intend to breastfeed and While breastfeeding was the norm in the early part of the 20th should reflect and incorporate the Baby-Friendly Hospital Initiative’s Ten century, rates declined after World War II, likely because of women Steps to Successful Breastfeeding. returning to the workforce as well as to the availability of commercial • Breastfeeding advocacy should reach into the community: breastfeeding infant formulas. Recognition of breastfeeding benefits grew during is a public health issue with evidence-based health and economic the 1970s, and rates more than doubled in the United States from benefits. 24.7% in 1971 to 59.7% in 1984 (Wright, 2001). The US Centers • All pediatricians must be knowledgeable about lactation management and be prepared to lead healthcare teams that support the for Disease Control and Prevention began monitoring annual breastfeeding dyad. breastfeeding rates through the National Immunization Survey • Every home-going infant should receive medical care at a pediatric (NIS) in 2001 and administered the first national survey of maternity office that has seamless access to appropriately trained lactation practices related to breastfeeding, the Maternity Practices in Infant specialists. Nutrition and Care Survey, in 2007 (Breastfeeding Data and • Breastfeeding education and support should be offered by trained Statistics, 2017). These figures can be compared with the Depart- peers and medical health providers, both prepartum and postpartum, ment of Health and Human Services’ Healthy People 2020 both in the community and in medical settings, and to the mother, her breastfeeding goals (Table 67.1); goals added for 2020 relate to partner, and all in her support system. reducing formula supplementation for breastfed infants, increasing • Changes in national health policy, such as availability of free lactation the proportion of workplaces with onsite lactation support, and services and paid maternity leave, hold promise for reducing health disparities associated with breastfeeding rates. increasing the proportion of live births at facilities with best practices • Each neonatal intensive care unit should have protocols and guidelines supporting lactation (to 8.1%) (Breastfeeding Data and Statistics, to support lactation for mothers of hospitalized neonates. 2015; US Department of Health and Human Services, 2015). In 2011 the US Department of Health and Human Services issued The Surgeon General’s Call to Action to Support Breastfeeding, which reviewed research on the multiple benefits of breastfeeding and E xclusive breastfeeding through 6 months of age, with described steps that family members, healthcare providers, research- continued breastfeeding to 12 months and beyond, is ers, employers, and communities can take to support breastfeeding recommended for all infants by the World Health Organi- (DHHS, 2011). While some states and population subgroups have zation (WHO; http://www.who.int/topics/breastfeeding/en/), the met initiation and continuation goals, disparities related to race, American Academy of Pediatrics (AAP; http://www.aap.org/ ethnicity, age, and socioeconomic status have not been eliminated breastfeeding/), and other professional organizations (World (CDC, 2015). Non-Hispanic African Americans and economically Health Organization, 2002; AAP, 2015; ACOG, Optimizing disadvantaged populations have the lowest breastfeeding rates for Support for Breastfeeding, 2016). Successful lactation depends on all measures at all infant ages, and women who are younger, supportive attitudes of pediatric and obstetric providers, evidence- unmarried, receive or are eligible for support from the Special based hospital practices, and the awareness that many mothers Supplemental Nutrition Program for Women, Infants, and Children will need assistance to establish and maintain breastfeeding. Much (WIC), and who have a lower educational level are less likely to information must be shared with new parents in the short post- initiate or continue breastfeeding (Table 67.2; CDC, 2015). partum hospital stay, so both prenatal and postdischarge breast- Culturally specific feeding beliefs also influence breastfeeding choice feeding education and support are essential. Caregivers should be (Cassidy and El Tom, 2015). An example from the Navajo culture trained to support and document breastfeeding, and newborns is the belief that either negative or positive maternal emotions can should have early follow-up at 3 to 5 days of age with a knowl- be transmitted through breast milk (Wright et al., 1993). Disparities edgeable healthcare provider and continuing lactation help (AAP, in breastfeeding rates are an important arena for public health 2015). initiatives (US Department of Health and Human Services, 2013). 991
992 PART XI I I Nutrition TABLE 67.1 Healthy People 2020 Infant Feeding Goals and Rates of Breastfeeding in the United States 2004 to 2012 Healthy People 2020 Objectives 2004 2006 2008 2010 2012 Breastfeeding Goals 81.9% initiation postpartum 73.1 ± 0.8 74.0 ± 0.9 74.6 ± 0.9 76.7 ± 1.2 80.0 ± 1.2 46.2% exclusive breastfeeding at 3 months 31.5 ± 0.9 33.6 ± 1.0 34.3 ± 1.0 37.1 ± 1.4 43.3 ± 1.6 25.5% exclusive breastfeeding at 6 months 12.1 ± 0.7 14.1 ± 0.8 14.6 ± 0.8 17.2 ± 1.2 21.9 ± 1.4 60.6% any breastfeeding at 6 months 42.1 ± 0.9 43.5 ± 1.1 43.5 ± 1.1 47.5 ± 1.4 51.4 ± 1.5 34.1% any breastfeeding at 12 months 21.4 ± 0.8 21.4 ± 0.8 21.4 ± 0.8 25.3 ± 1.3 29.2 ± 1.4 Additional Goals 14.2% of breastfed infants within first 48 h 23.5 ± 1.0 24.2 ± 1.1 25.1 ± 1.1 22.8 ± 1.4 19.1 ± 1.3 38.0% of workplaces with lactation support (25% reporting in 2009 serving as the baseline; other data not available) Numbers represent the percentage of US children who were breastfed, by birth year, National Immunization Survey, United States (percent age ± half 95% confidence interval); see site for additional methodological details of the survey, and see http://www.cdc.gov/breastfeeding/data/reportcard.htm for annually updated breastfeeding rates. From HealthyPeople.gov. Maternal, Infant and Child Health. http://www.healthypeople.gov/2020/topics-objectives/topic/maternal-infant-and-child-health/objectives; and Centers for Disease Control and Prevention. Breastfeeding among U.S. children born 1999-2005, CDC National Immunization Survey. http://www.cdc.gov/breastfeeding/data/NIS_data/index.htm. advertising of breast milk substitutes (i.e., formula), effectively • BOX 67.1 Ten Steps to Successful Breastfeeding increased breastfeeding rates worldwide (World Health Organization, Step 1: Have a written breastfeeding policy that is routinely communicated to UNICEF and Wellstart International, 2009). Adherence to these all healthcare staff. evidence-based maternity practices significantly increases the Step 2: Train all healthcare staff in the skills necessary to implement this likelihood of mothers initiating breastfeeding, exclusively breastfeed- policy. ing, and breastfeeding through 6 months (DiGirolamo et al., 2008; Step 3: Inform all pregnant women about the benefits and management of Sinha et al., 2015; Yotebieng et al., 2015). While implementation breastfeeding. of all ten steps is optimal, breastfeeding rates increase with the Step 4: Help mothers initiate breastfeeding within 1 hour of birth. number of steps practiced, including with a single step, such as Step 5: Show mothers how to breastfeed and how to maintain lactation even if they are separated from their infants. initiating breastfeeding within 1 hour of birth with skin-to-skin Step 6: Give newborns no food or drink other than breast milk, unless contact (Kramer et al., 2001; Philipp et al., 2001; Rosenberg et al., medically indicated. 2008; Moore et al., 2012; Olaiya et al., 2016). Possible expansion Step 7: Practice rooming-in—allow mothers and infants to remain together 24 of a modified Ten Steps to Successful Breastfeeding program to hours a day. neonatal intensive care units (NICUs) has been proposed (Nyqvist Step 8: Encourage breastfeeding on demand. et al., 2013; World Health Organization, 2015). State health Step 9: Give no pacifiers or artificial nipples to breastfeeding infants. departments have begun to create programs to support Ten Steps Step 10: Foster the establishment of breastfeeding support groups, and refer to Successful Breastfeeding practices (e.g., http://texastenstep.org/), mothers to them on their discharge from the hospital or birth center. and the number of birthing hospitals designated as baby friendly From the Baby Friendly Hospital Initiative “Ten Steps to Successful Breastfeeding for Hospitals” as (by Baby-Friendly USA Inc.) is increasing (Baby-Friendly, 2015). outlined by UNICEF/World Health Organization. Available at https://www.babyfriendlyusa.org/ Systematic reviews suggest that breastfeeding support is optimal about-us/baby-friendly-hospital-initiative/the-ten-steps. when offered prepartum and postpartum and in multiple settings: essential interventions include counseling by peers and health providers, BFHI practices, and actions that mobilize community awareness (Sinha et al., 2015). Counseling and education in the Interventions to Support Breastfeeding home and family environment promote breastfeeding initiation, Initiation, Exclusivity, and Continuation exclusivity, and continuation; family and social support alone, surprisingly, had no significant impact (Sinha et al., 2015). In response to extensive formula marketing in the developing world WIC initiatives, including enhanced maternal food packages with resulting high rates of infant morbidity and mortality, the for breastfeeding mothers and peer counseling (Loving Support), World Health Assembly created the International Code of Marketing hold promise, as do the Affordable Care Act mandates covering of Breastmilk Substitutes (1981) to promote ethical marketing of breastfeeding education and supplies and reasonable break time formula products (World Health Organization, 1981). In 1992 for “nonexempt” hourly employees to express milk (Sections 2713 United Nations International Children’s Emergency Fund and the and 4207) (Murtagh and Moulton, 2011; Hawkins et al., 2015). World Health Organization (WHO) developed the Baby-Friendly Workday strategies that include feeding the infant directly from Hospital Initiative (BFHI), an international program to promote the breast appear more effective than pumping only (Fein et al., breastfeeding-supportive policies for birthing hospitals (Box 67.1; 2008). However, maternal employment outside the home, in general, Willumsen, 2013). The BFHI “10 steps” in combination with an is associated with decreased breastfeeding initiation and continuation “11th step,” the WHO International Code of Marketing of (Ogbuanu et al., 2011; CDC, 2016). Public policy changes can Breastmilk Substitutes, which protects against free provision and increase national breastfeeding rates: provision of paid maternity
CHAPTER 67 Breastfeeding 993 TABLE 67.2 Rates of Any and Exclusive Breastfeeding by Sociodemographic Factors Among Children Born in 2012 ANY BREASTFEEDING EXCLUSIVE BREASTFEEDING Through 3 Through 6 Ever Breastfed At 6 Months At 12 Months Months Months Sociodemographic Factors n % ± Half 95% CI % ± Half 95% CI % ± Half 95% CI n % ± Half 95% CI % ± Half 95% CI US National 15,141 80.0 ± 1.2 51.4 ± 1.5 29.2 ± 1.4 14,768 43.3 ± 1.6 21.9 ± 1.4 Race/Ethnicity Hispanic 2788 82.4 ± 2.8 51.4 ± 3.7 27.9 ± 3.6 2749 40.3 ± 3.8 20.8 ± 3.3 Non-Hispanic white 8811 83.0 ± 1.3 55.8 ± 1.8 32.8 ± 1.8 8546 48.0 ± 1.9 24.4 ± 1.7 Non-Hispanic black 1476 66.4 ± 3.8 35.3 ± 4.0 16.9 ± 3.1 1460 33.4 ± 4.1 13.9 ± 2.9 Non-Hispanic Asian 683 83.2 ± 7.6 65.6 ± 7.7 42.3 ± 7.0 662 46.5 ± 7.5 26.9 ± 7.1 Non-Hispanic Hawaiian/ 96 83.9 ± 14.1 32.6 ± 19.0 14.4 ± 9.0 95 43.3 ± 24.1 11.8 ± 9.5 Pacific Islander Non-Hispanic American 217 71.5 ± 12.6 28.8 ± 11.7 17.9 ± 8.9 212 27.4 ± 11.8 12.5 ± 6.5 Indian/Alaska Native Two or more races 1070 75.4 ± 6.5 46.2 ± 6.2 25.3 ± 5.4 1044 41.4 ± 6.3 23.0 ± 5.6 Maternal Education Less than high school 1575 69.1 ± 3.8 40.3 ± 4.5 21.2 ± 3.9 1559 32.8 ± 4.5 16.1 ± 3.9 High school graduate 2755 71.1 ± 3.1 38.2 ± 3.3 20.0 ± 2.8 2696 33.5 ± 3.1 16.3 ± 2.5 Some college/technical school 3924 81.2 ± 2.3 45.9 ± 3.2 24.2 ± 2.8 3814 41.2 ± 3.2 19.5 ± 2.7 College graduate 6887 91.2 ± 1.1 70.3 ± 1.9 43.2 ± 2.3 6699 57.2 ± 2.2 30.6 ± 2.2 Maternal Age
994 PART XI I I Nutrition leave for employed women increases breastfeeding exclusivity and Nutritional Aspects duration, and longer maternity leaves are associated with increased breastfeeding initiation (Fein et al., 2008; DHHS, 2011; Ogbuanu The human milk model is used to design the composition of breast et al., 2011; Breastfeeding Promotion and Employment, 2016; milk substitutes, because the goal for infant nutrition through the Huang and Yang, 2015; Nandi et al., 2016). The United Nations first year is to mimic the body composition of the breastfed infant. International Labor Organization recommends 18 weeks of paid Human milk has a dynamic nutrient composition that changes maternity leave, a “reasonable goal” that could push the United throughout lactation, over the course of a day, and within a feeding States closer to Healthy People breastfeeding targets (DHHS, 2011; and differs between women. Components of human milk have US Department of Health and Human Services, 2017). multiple nutritional and immunologic functions. A reference tabulation of the composition of human milk comparing early The Evidence to Support Breastfeeding and more mature milk is given in Table 67.3 (Picciano, 2001). In the first few weeks after birth, the total protein content of milk More than 1 decade ago, exclusive breastfeeding through 6 months from mothers who deliver prematurely (preterm milk) is greater of age was identified as the most effective international preventive than that of milk obtained from women delivering at term (term health intervention for children younger than 5 years, with the milk), and the total protein content in both declines similarly to potential to prevent 13% of deaths of children younger than 5 approach that in what is called mature milk (Ballard and Morrow, years worldwide (Jones et al., 2003). Human milk has widely 2013). Milk protein content is not related to maternal diet acknowledged benefits in high-, middle-, and low-income countries but increases with maternal body mass index (BMI) (Nommsen with respect to infant nutrition, infant survival, gastrointestinal et al., 1991). function, host defense, neurodevelopment, and psychological The protein quality of human milk (whey 70%, casein 30%) well-being. The benefits of exclusive breastfeeding, as well as a differs from that of bovine milk (82% casein, 18% whey). Caseins “dose-dependent” effect of breastfeeding duration and of partial are proteins with low solubility in gastric acid, while whey proteins breastfeeding, are well documented (Sankar et al., 2015). Maternal remain in solution after acid precipitation. The whey protein fraction health benefits increase with the number of months of lactation is more easily digested and promotes rapid gastric emptying. It and are also well described (Chowdhury et al., 2015). There is also provides lower concentrations of phenylalanine, tyrosine, and insufficient evidence to endorse formula supplementation as a methionine and higher concentrations of taurine than the casein change in practice from exclusive breastfeeding (Becker and fraction and serves as a model for enteral and parenteral amino Remmington, 2014). However, health providers can elicit parents’ acid mixtures. The major whey protein in human milk is perspectives about the challenges of exclusive breastfeeding and α-lactalbumin. Lactoferrin, lysozyme, and secretory immunoglobulin provide scientifically based guidance and personalized support, A (sIgA) are specific immunoactive human whey proteins that recognizing that any breast milk (including colostrum) gives a resist proteolytic digestion and thus serve as a first line of defense meaningful health benefit (Flaherman and Fuentes-Afflick, 2014). by lining the gastrointestinal tract (Brandtzaeg, 2010). The success of the United Nations Millennium Development Goals, The lipid system in human milk, responsible for providing with a reduction in the number of deaths of children younger approximately 50% of the calories in the milk, is structured to than 5 years from 12.7 million per year in 1990 to 5.9 million facilitate fat digestion and absorption. The lipid system is composed per year in 2015, is multifactorial, yet breastfeeding plays a large of an organized milk fat globule, bile salt–stimulated lipase, and current and larger potential role (World Health Organization Media a pattern of fatty acids (high in palmitic [C16:0], oleic [C16:1 Centre, 2015). Exclusive breastfeeding (0 to 5 months) is increasing ω9], linoleic [C18:2 ω6], and linolenic [C18:3 ω3] acids) char- by 1% annually in the Millennium Development Goals–tracked acteristically distributed on the triglyceride molecule (C16:0 at countries, with median coverage of 39% (Requejo et al., 2015). the 2-position of the molecule). That distribution is unique to Each of the 2030 United Nations Sustainable Development Goals, human milk. When triglycerides are hydrolyzed in the intestine, for example, “Zero Hunger,” can be linked to and supported by free fatty acids are released. Palmitic acid, in particular, is a prevalent breastfeeding. The global societal and economic benefits of full fatty acid that has a predilection to bind minerals such as calcium breastfeeding are remarkable and are yet to be fully realized. to form insoluble “soaps.” The soap formation therefore reduces fat absorption and mineral (calcium) absorption. The palmitic acid in human milk triglyceride, however, is mainly found at the Studies Supporting Benefits of Breastfeeding 2-position. Human milk lipases hydrolyze the triglyceride molecule Methodological issues impact research on health outcomes related but leave the palmitic acid bound to the glycerol backbone. The to breastfeeding. These include (1) duration of breastfeeding recall, resulting monoglyceride is well absorbed. The fat blends in formula which is inversely related to accuracy (Burnham et al., 2014), (2) must be modified to compensate for poor fat absorption, so they use of standardized definitions for breastfeeding duration, exclusivity, contain greater quantities of medium-chain-length fatty acids, and method of feeding (expressed or at breast), which facilitates which are absorbed passively, in an attempt to mimic the superior comparisons (Noel-Weiss et al., 2012), (3) the need to identify fat absorption from human milk. and adjust for confounders such as socioeconomic status, (4) study The pattern of fatty acids in human milk is also unique in design (e.g., retrospective or cross-sectional studies are weaker than its composition of very long chain polyunsaturated fatty acids. prospective longitudinal ones), and (5) concerns for reverse causality. Arachidonic acid (C20:4 ω6) and docosahexaenoic acid (C22:6 ω3), Since it is nearly impossible and undoubtedly unethical to randomize found in human milk but not bovine milk and added to formula, mothers to breastfeed or not, unmeasured confounding occurs; are constituents of retinal and brain phospholipid membranes randomization by health system has been one alternative approach and have been associated with improved visual function and, (Kramer et al., 2001; Yotebieng et al., 2015). The preponderance potentially, neurodevelopmental outcome (Koletzko et al., 2008). of evidence supports the benefits detailed in the following The fat content of milk varies with maternal diet and throughout sections. the feed, with hindmilk (the last part of the feed) containing
CHAPTER 67 Breastfeeding 995 TABLE 67.3 Representative Values for Constituents of Human Milk Constituent Early Milk Mature Milk Constituent Early Milk Mature Milk Energy (kcal/L) 650–700 Linoleic acid (C18:2 ω6) 8.9 11.3 Carbohydrate Arachidonic acid (C20:4 ω6) 0.7 0.5 Lactose (g/L) 20–30 67 Water-Soluble Vitamins Glucose (g/L) 0.2–1.0 0.2–0.3 Ascorbic Acid (mg/L) 100 Oligosaccharides (g/L) 22–24 12–14 Thiamin (µg/L) 20 200 Total nitrogen (g/L) 3.0 1.9 Riboflavin (µg/L) 400–600 Nonprotein nitrogen (g/L) 0.5 0.45 Niacin (mg/L) 0.5 1.8–6.0 Protein nitrogen (g/L) 2.5 1.45 Vitamin B6 (mg/L) 0.09–0.31 Total protein (g/L) 16 9 Folate (µg/L) 80–140 Casein (g/L) 3.8 5.7 Vitamin B12 (µg/L) 0.5–1.0 β-Casein (g/L) 2.6 4.4 Pantothenic acid (mg/L) 2–2.5 κ-Casein (g/L) 1.2 1.3 Biotin (µg/L) 5–9 α-Lactalbumin (g/L) 3.62 3.26 Fat-Soluble Vitamins Lactoferrin (g/L) 3.53 1.94 Retinol (mg/L) 2 0.3–0.6 Albumin (g) 0.39 0.41 Carotenoids (mg/L) 2 0.2–0.6 sIgA (g/L) 2.0 1.0 Vitamin K (µg/L) 2–5 2–3 IgM (g/L) 0.12 0.2 Vitamin D (µg/L) 0.33 IgG (g/L) 0.34 0.05 Vitamin E (mg/L) 8–12 3–8 Total lipids (%) 2 3.5 Minerals Triglyceride (% total lipids) 97–98 97–98 Calcium (mg/L) 250 200–250 Cholesterola (% total lipids) 0.7–1.3 0.4–0.5 Magnesium (mg/L) 30–35 30–35 Phospholipids (% total lipids) 1.1 0.6–0.8 Phosphorus (mg/L) 120–160 120–140 Fatty Acids (wt%) 88 88 Sodium (mg/L) 300–400 120–250 Total saturated fatty acids (%) 43–44 44–45 Potassium (mg/L) 600–700 400–550 Palmitic acid (C16:0) 20 Chloride (mg/L) 600–800 400–450 Monounsaturated fatty acids (%) 40 Iron (mg/L) 0.5–1.0 0.3–0.9 Oleic acid (C18:1 ω9) 32 31 Zinc (mg/L) 8–12 1–3 Polyunsaturated fatty acids (%) 13 14–15 Copper (mg/L) 0.5–0.8 0.2–0.4 Total ω3 fatty acids (%) 1.5 1.5 Manganese (µg/L) 5–6 3 Linolenic acid (C18:3 ω3) 0.7 0.9 Selenium (µg/L) 40 7–33 Eicosapentaenoic acid (C22:5 ω3) 0.2 0.1 Iodine (µg/L) 150 Docosahexaenoic acid (C22:6 ω3) 0.5 0.2 Fluoride (µg/L) 4–15 Total ω6 fatty acids (%) 11.6 13.06 a The cholesterol content of human milk ranges from 100 to 200 mg/L in most samples of human milk after day 21 of lactation. IgG, Immunoglobulin G; IgM, immunoglobulin M; Kcal, kilocalorie; sIgA, secretory immunoglobulin A. Modified from Picciano MF. Appendix: representative values for constituents of human milk. Pediatr Clin North Am. 2001;48:263–272 and Schanler RS, Krebs N, Mass S, eds. AAP/ACOG Breastfeeding Handbook for Physicians. Elk Grove, IL: American Academy of Pediatrics; 2013:77.
996 PART XI I I Nutrition two to three times more than the initial milk (foremilk) (Saarela with multiple milk transfers and tube feedings (Greer et al., 1984; et al., 2005). Schanler, 1988). Gastrointestinal advantages of human milk as The carbohydrate composition of human milk is important as a compared with preterm formula include faster gastric emptying, nutritional source of lactose and for the presence of oligosaccharides. less feeding intolerance, and fewer days to full enteral feeds (Schanler A softer stool consistency, more nonpathogenic fecal flora, and et al., 1999; Tudehope, 2013; Assad et al., 2016). However, the improved mineral absorption have each been attributed to small concentrations of protein, sodium, and zinc decline throughout quantities of unabsorbed lactose. Human milk oligosaccharides lactation, and the nutrient needs of the premature infant remain are bioactive carbohydrate polymers (also including glycoproteins) higher than those of term infants until after term postmenstrual that help protect the infant because their structure mimics specific age. Therefore in contrast to the term infant, this physiologic bacterial antigen receptors and prevent bacterial attachment to decline in milk protein and micronutrient content precedes any the host mucosa. Some examples of human milk oligosaccharides reduction in the premature infant’s needs. For the very low birth (HMOs) include fucosylated glycans that specifically inhibit binding weight (VLBW;
CHAPTER 67 Breastfeeding 997 TABLE Nutrient Composition of Preterm Human Milk (relative risk [RR] 8.66) or who were partially breastfed (RR 4.56) 67.4 With and Without Fortifier and even who were predominantly but not exclusively breastfed (RR 1.7), each in comparison with exclusively breastfed infants Mature Mature aged 0 to 5 months. Children aged 6 to 23 months who were Preterm Preterm Preterm never breastfed, as compared with ever breastfed, had a 2.1 times Human Human Human Milk higher risk of death (Sankar et al., 2015). In developing countries Milk Milk Plus Human the incidence, prevalence, and mortality because of diarrheal illnesses (1 Week) (1 Month) Milk Fortifiera are significantly decreased by breastfeeding. When compared with Volume (mL) 100 100 100 exclusive breastfeeding, mortality caused by diarrhea was higher among infants who were never breastfed (RR 10.52), partially Energy (kcal) 67 69 83 breastfed (RR 4.62), or predominantly breastfed (RR 2.28) Protein (g) 2.4 1.5 2.5–2.6 (Lamberti et al., 2011). These data demonstrate the “dose depen- dent” benefit of breast milk for prevention of death caused by Whey/casein (%) 70/30 70/30 70/30 diarrheal illness. Never breastfed infants aged 0 to 11 months, as Fat (g) 3.8 3.6 4.0–4.6 compared with those who were predominantly breastfed, were also at greater risk of death from diarrhea illness (RR 11.73) (Lamberti Medium-chain 2 2 11–17 et al., 2011). Even when only infants in the developed world are triglycerides (%) considered, the risk of nonspecific gastrointestinal disease is lower Carbohydrate (g) 6.1 6.7 7.1–8.5 among infants aged 0 to 11 months who were ever breastfed as compared with those who were never breastfed (Ip et al., 2007). Lactose (%) 100 100 80–85 Exclusive breastfeeding for the first 6 months of life reduces the Calcium (mg) 25 29 119–146 risk of otitis media in children younger than 2 years, and both Phosphorus (mg) 14 9.3 59–76 longer duration and any versus no breastfeeding are protective (Bowatte et al., 2015); this benefit may extend through age 6 years Magnesium (mg) 3.1 2.4 3.4–9.4 (Li et al., 2014). Worldwide, the risk of acute lower respiratory Sodium (mEq, mmol) 2.2 0.9 1.6 tract infection (LRTI) caused by respiratory syncytial virus was increased by not breastfeeding (Shi et al., 2015); the risk of death Potassium (mEq, mmol) 1.8 1.3 2–2.9 because of pneumonia was higher for both never versus exclusively Chloride (mEq, mmol) 2.6 1.5 1.9–2.6 breastfed infants aged 0 to 5 months and for never versus ever breastfed children aged 6 to 23 months (Lamberti et al., 2013). Zinc (µg) 500 215 935–1215 In developed countries, after adjustment for day care, smoke Copper (µg) 80 51 95–221 exposure, and socioeconomic status, the risk of hospitalization because of LRTI was significantly lower for infants exclusively Vitamin A (IU) 560 227 847–1177 breastfed for 4 months versus those receiving no breast milk (Ip Vitamin D (IU) 4 1.2 122–151 et al., 2007; Table 67.6). Clinical studies throughout the world and over several decades Vitamin E (mg) 1.0 0.3 3.5–4.9 have also suggested a decrease in the rates of morbidities in pre- a Enfamil human milk fortifier (Mead Johnson Nutritionals, Evansville, Indiana) and Similac mature infants fed human milk (Narayanan et al., 1980; Hylander human milk fortifier (Ross Laboratories, Columbus, Ohio) are powdered formulations that use et al., 1998; El-Mohandes et al., 1998; Ronnestad et al., 2005). bovine protein (based on addition of four packets to 100 mL mature preterm human milk). Pasteurized donor milk, rather than preterm formula, is now recom- Liquid bovine milk protein–based fortifiers (Enfamil human milk fortifier acidified liquid and mended for infants whose mothers are unable to provide full volumes Similac human milk fortifier concentrated liquid) and liquid human milk–based fortifiers are also available (Prolact+ H2MF® all-liquid milk fortifier [http://www.prolacta.com/]). Liquid of breast milk for their premature infant (Arslanoglu et al., 2013; fortifiers displace and hence reduce part of the volume of human milk that the infant receives. Quigley and McGuire, 2014; AAP, 2015) Methodological issues, IU, International unit; Kcal, kilocalorie; mEq, milliequivalent. including differing definitions of “human milk” (mother’s own vs From Gross SJ, David RJ, Bauman L, Tomarelli RM. Nutritional composition of milk produced donor, frozen vs fresh, mixed with formula) and of human milk by mothers delivering preterm. J Pediatr. 1980;96:641–644; Butte NF, Garza C, Johnson intake volume (ml/kg per day vs daily percentage of enteral or all CA, Smith EO, Nichols BL. Longitudinal changes in milk composition of mothers delivering preterm and term infants. Early Hum Dev. 1984a;9:153–162; Specker BL, Greer F, Tsang intake) create difficulties in the interpretation of results, yet data RC. Vitamin D. In: Tsang RC, Nichols BL, eds. Nutrition During Infancy. Philadelphia, PA: from studies that quantified human milk intakes suggest that the Hanley & Belfus; 1988: 264–276; Schanler RJ. Water-soluble vitamins for premature infants. protective effect is (1) optimized by an exclusive human milk diet In: Tsang RC, Uauy R, Koletzko B, Zlotkin S, eds. Nutrition of the Preterm Infant. Scientific and (2) likely dose dependent. Basis and Practical Guidelines. Cincinnati, OH: Digital Educational Publishing; 2005:173–199; and Schanler RJ, Atkinson SA. Human milk. In: Tsang RC, Uauy R, Koletzko B, Zlotkin S, eds. Premature infants who receive their own mother’s milk have a Nutrition of the Preterm Infant. Scientific Basis and Practical Guidelines. Cincinnati, OH: Digital significantly lower risk of NEC after adjustment for gestational Educational Publishing; 2005:333–356. age, and metaanalysis confirms the magnitude of these results (Ip et al., 2007; Sisk et al., 2007; Meinzen-Derr et al., 2009). Donor human milk is also protective against NEC in premature infants when compared with formula (see later) (Arslanoglu et al., 2013; In both developing and developed countries, there is a reduction Quigley and McGuire, 2014; Kantorowska et al., 2016). The risk in all-cause infection-related mortality attributable to breastfeeding, of late-onset sepsis is likely reduced by human milk feeding (Schanler with a clear “dose response.” The dose response has been categorized et al., 1999; Furman et al., 2003; Ronnestad et al., 2005; Cossey as exclusively, predominantly, partially, or never breastfed. The et al., 2013; Pammi and Weisman, 2015). NICU length of stay relative risk of death due to all infectious causes is significantly is shorter for human milk–fed infants: a direct relationship between greater in infants aged 0 to 5 months who were never breastfed lower risk of morbidity and dose of human milk (19% lower risk
998 PART XI I I Nutrition TABLE 67.5 Selected Bioactive Factors in Human Milk Immunoglobulins Secretory IgA Specific antigen-targeted antiinfectives IgG Antimicrobial IgM Complement activation Lactoferrin Immunomodulation, iron chelation, antimicrobial action, antiadhesive, trophic for intestinal growth Lactadherin Antiviral and antiinflammatory Lysozyme Bacterial lysis, immunomodulation κ-Casein Antiadhesive, bacterial flora Oligosaccharides Stimulate colonization by beneficial organisms Gangliosides and glycosaminoglycans Prevent infections a Cytokines Antiinflammatory, proinflammatory, epithelial barrier function, recruit neutrophils Macrophages Antiinfectious and activate T cells Growth Factors Epidermal growth factor Luminal surveillance, repair of intestine Transforming growth factor Promotes epithelial cell growth (transforming growth factor-α) Suppresses lymphocyte function (transforming growth factor-β) Nerve growth factor Promotes growth of neurons Vascular endothelial growth factor Promotes angiogenesis and tissue repair Insulin-like growth factor Promotes growth Macrophage migratory inhibitory factor Prevents macrophage movement Hormones Adiponectin Reduction of infant BMI, antiinflammatory Leptin Regulation of infant BMI and appetite Calcitonin Promotes development of enteric neurons Somatostatin Regulates growth of gastric epithelium Enzymes Platelet-activating factor acetylhydrolase Blocks action of platelet-activating factor Glutathione peroxidase Prevents lipid oxidation Nucleotides Enhance antibody responses, bacterial flora Vitamin A, E, C Antioxidants Glutamine (amino acid) Intestinal cell fuel, immune responses Lipids Antiinfective properties Mucins 1 and 4 Block infectious agents a Includes interleukins 6, 7, 8, and 10, tumor necrosis factor-α, transforming growth factor-β, and interferon gamma. BMI, Body mass index. Modified from Schanler RS, Krebs N, and Mass S, eds. AAP/ACOG Breastfeeding Handbook for Physicians. Elk Grove, IL: American Academy of Pediatrics; 2013:77 and Ballard O, Morrow AL. Human milk composition: nutrients and bioactive factors. Pediatr Clin North Am. 2013;60:49–74. for each additional 10 mL of human milk kg/day) and significantly infant) (Patel et al., 2013; Assad et al., 2016). The rates of both lower NICU costs has been documented, and exclusive human any-stage and severe retinopathy of prematurity are decreased by milk feeding, as compared with all other diets, was associated with human milk feeding, with a dose response noted (Zhou et al., reduced risk of NEC (P < .011), fewer days to full feeds (P < 2015). Exclusive human milk feeding is also associated with reduced .001), and lower hospitalization cost (savings up to $106,968 per risk of bronchopulmonary dysplasia (Spiegler et al., 2016).
CHAPTER 67 Breastfeeding 999 TABLE 67.6 Benefits of Breastfeeding for Infants and Mothers 95% Confidence Condition Comparison Odds Ratio Interval Maternal Benefits All for each additional 12 months of lactation Breast cancer 0.74 0.69–0.79 Ovarian cancer 0.63 0.56–0.71 Hypertension 0.89 0.84–0.93 Hyperlipidemia 0.81 0.76–0.87 Cardiovascular disease 0.80 0.65–0.97 Type 2 diabetes RR 0.91 0.86–0.96 Infant/Child Benefits Infectious Diseases All cause 0–5 months Never vs exclusive BF RR 8.66 3.19–23.5 All cause 6–23 months Never vs ever BF RR 2.09 1.68–2.60 Otitis media
1000 PART XI I I Nutrition risk (Tham et al., 2015). Data are conflicting regarding allergic been correlated with the receipt of fortified human milk during disease, but metaanalysis shows reduced risk of asthma at age 5 hospitalization. The magnitude of the effect at 18 to 22 months years to age 18 years for ever versus never breastfeeding and for was greatest in the highest quintile (>80%), who averaged 110 mL/ more versus less breastfeeding, with no impact of stratification by kg per day of human milk, and at 30 months the effect persisted family atopy (Lodge et al., 2015). Reduced risk of eczema before such that for every 10 mL/kg per day increase in human milk, age 2 years, but not after, was associated with exclusive breastfeeding the Mental Developmental Index increased by 0.59 points, the for 3 to 4 months (Lodge et al., 2015). Breastfeeding does not Psychomotor Developmental Index increased by 0.56 points, and specifically reduce the risk of food allergies, although it appears the total behavior percentile score increased by 0.99 points (Vohr to reduce the risk of generalized allergic disease before age 5 years et al., 2006, 2007). (Lodge et al., 2015). Mother–infant bonding is also enhanced during breastfeeding There appears to be an inverse relationship between exclusivity (Feldman et al., 2007; Galbally et al., 2011). The likely biologic and duration of breastfeeding and the risk of obesity and over- basis for this universal observation is oxytocin, which causes the weight in childhood and adulthood (metaanalyses showing pooled milk ejection reflex during nursing, and serves as a central odds ratio (OR) of 0.74; 95% confidence interval (CI) 0.70–0.78) neurotransmitter that directly affects maternal nurturing behaviors, (Ip et al., 2007; Horta et al., 2015b). This association is stronger mother–infant social interaction, gaze, vocalizations, and affectionate for studies assessing exclusive breastfeeding and for those reporting touch (Britton et al., 2006). children as compared with adults and is weaker for studies with large numbers of participants (>1500) and for those that adjusted Infant and Childhood Mortality the data for relevant confounders, including maternal BMI, birth weight for gestational age, and socioeconomic factors. Although The risk of all-cause death worldwide was higher among children it is difficult to eliminate the possibility of residual confounding aged 0 to 5 months for those who were not breastfed (RR 14.4), by unmeasured lifestyle factors, high-quality studies from high-, partially breastfed (RR 4.8), and predominantly breastfed (RR medium-, and low-income settings show a 13% reduction in the 1.5) as compared with those who were exclusively breastfed (Sankar risk of obesity with breastfeeding (summary OR 0.87; 95% CI et al., 2015). Children aged 6 to 23 months who were not breastfed 0.76–0.99) (Ip et al., 2007; Horta et al., 2015b). Biologically had higher all-cause mortality than those who continued breastfeed- plausible mechanisms for this effect include more optimal self- ing: mortality decreased with exclusivity and duration of breastfeed- regulation of energy intake when feeding at the breast (Li et al., ing, but any breastfeeding was protective (Sankar et al., 2015). 2012), higher protein/energy intake among formula-fed than Breastfeeding also appears protective against sudden infant death breastfed infants leading to neonatal obesity and hence childhood syndrome (SIDS) (Hauck et al., 2011). On metaanalysis the risk obesity (Heinig et al., 1993; Rolland-Cachera et al., 1995; Stettler of SIDS was lowered for exclusively breastfed infants and for infants et al., 2002), differences in release of insulin and other gut and with any breastfeeding (Hauck et al., 2011). Although a direct pancreatic hormones in formula-fed versus breastfed infants that mechanism is not known, the effect is strong and dose dependent may alter fat deposition patterns (Lucas et al., 1980), and reduced and does not appear only as a marker for confounders such as risk of type 2 diabetes mellitus with breastfeeding (Horta et al., passive smoking or demographic factors. 2015b). Additionally, hormones in breast milk, including leptin, adiponectin, and ghrelin, appear to regulate appetite, growth, fat Maternal Benefits deposition, and energy balance, which may explain differences in early body composition and later BMI between breastfed and There are numerous benefits of breastfeeding for the mother (Table formula-fed infants (Savino et al., 2009; Kon et al., 2014). Neither 67.6). Lactation has a beneficial effect on lipid and glucose metabo- blood pressure nor cholesterol levels in later life appear to lism and is associated with significant reduction in the risk of type be impacted by breastfeeding (Owen et al., 2008; Horta et al., 2 diabetes and cardiovascular morbidities (Schwarz et al., 2009; 2015b). Aune et al., 2014; Chowdhury et al., 2015). Multiple studies have documented a significantly decreased incidence of premenopausal breast and ovarian cancer in women who have breastfed (Col- Neurobehavioral Aspects laborative Group on Hormonal Factors in Breast Cancer, 2002; Whether an improvement in cognitive ability is attributable to Chowdhury et al., 2015). Neither rapid postpartum weight loss nor breastfeeding and/or human milk has been difficult to determine. changes in bone mineral density are attributable to breastfeeding; Disagreement has remained even when (1) results are adjusted for however, the risk of postpartum hemorrhage may be decreased by the key confounders of maternal intelligence, education, and breastfeeding combined with skin-to-skin care, although additional socioeconomic class, and (2) only studies meeting rigorous standards study is needed (Chowdhury et al., 2015; Abedi et al., 2016). are included (Ip et al., 2007). However, metaanalysis using strict Postpartum depression both predicts and is predicted by cessation study criteria found that breastfeeding was positively associated of breastfeeding; it is not known whether breastfeeding can directly with an average gain of 3.44 points (95% CI 2.30–4.58 points) reduce postpartum depression (Dias and Figueiredo, 2015). Exclusive on intelligence testing in childhood and adolescence for breastfed breastfeeding delays resumption of normal ovarian cycles and the individuals. When only the highest-quality studies (n = 4 with return of fertility, probably because of an elevated prolactin level sample size >500, breastfeeding recall time
CHAPTER 67 Breastfeeding 1001 Societal Impact of Breastfeeding • BOX 67.2 Contraindications to Breastfeeding From a national economic perspective, it has been estimated that Maternal if all infants enrolled in the WIC program were breastfed exclusively Untreated active maternal military tuberculosis: Refrain from breastfeeding for the first 6 months of life, food package costs would be reduced or infant contact until treated and no longer contagious, approximately by 18%, realizing approximately $1.2 million of savings (Institute 2 weeks. of Medicine, 2010; Hartmann et al., 2012; US Department of Active herpetic lesions on the breast: Refrain from breastfeeding until active lesions on breast and nipple have resolved. Vaginal herpes is not a Agriculture, Food and Nutrition Service, 2015). Additional savings contraindication. can accrue from a reduction in household expenditure on formula Active varicella (chickenpox) lesions on the breast: Express milk until lesions and healthcare costs, with less parental work absence because of are crusted over; administer varicella immunoglobulin to infant. the decreased rates of illness experienced by breastfed infants; costs Active human immunodeficiency virus (HIV) infection: Active HIV infection is not significantly drop with every additional month of breastfeeding an absolute contraindication in developing countries.a and each month delay in return to work after 3 months (Cattaneo Active human T-lymphotrophic virus (types 1 and 2) infection et al., 2006). Cost analyses estimating the burden of suboptimal Use of illicit drugs is an absolute contraindication.b breastfeeding for maternal health alone predicted a $733.7 million Drug-free methadone-maintained women can breastfeed. direct loss to society; similar analyses showed that if 80% of US Cancer chemotherapy or radiation treatment: For the duration of treatment, families exclusively breastfed for 6 months, $10.5 billion would seek consultation for diagnostic studies using radiation to determine duration for which expressed milk must be discarded. be saved and 741 infant deaths would be prevented (Bartick and Acute maternal illness with swine flu (H1N1 flu):c Reinhold, 2010; Bartick et al., 2013). Thus extraordinary societal If the mother is ill, her infant should ideally be fed the mother’s expressed and economic incentives support attainment of full breastfeeding breast milk by someone who is not ill. for each infant–mother dyad. Infant Contraindications to Breastfeeding Galactosemia: Lactose cannot be ingested and is the carbohydrate of breast milk. Few true contraindications to breastfeeding exist (Box 67.2; AAP/ Other inborn errors of metabolism require consultation regarding the specific ACOG, 2012; CDC, 2016). Mothers with fever or other minor metabolic defect(s). illness should be permitted to breastfeed, since the infant has already a “Since 2010, the World Health Organization has recommended that mothers who are HIV-infected been exposed to the infectious agent and will be able to benefit take ARVs [anti-retroviral medications] and exclusively breastfeed their babies for 6 months, then from the mother’s developing immunity if breastfeeding can con- introduce appropriate complementary foods and continue breastfeeding up to the child’s first birthday…. Even when ARVs are not available, mothers should be counseled to exclusively tinue. Few maternal medications contraindicate breastfeeding, and breastfeed for 6 months and continue breastfeeding thereafter unless environmental and social alternative choices are available in most cases; the National Institutes circumstances are safe for, and supportive of, feeding with infant formula.” World Health of Health US National Library of Medicine Drugs and Lactation Organization recommendation available at http://www.who.int/mediacentre/factsheets/fs342/en/. Database (https://toxnet.nlm.nih.gov/newtoxnet/lactmed.htm) is b The American Academy of Obstetricians and Gynecologists (Committee opinion no. 637: Marijuana the optimal resource and should be consulted (US National Library use during pregnancy and lactation. American College of Obstetricians and Gynecologists. Obstet Gynecol 2015;126:234–8) and the American Academy of Pediatrics (http://pediatrics. of Medicine, 2015). Mothers who have undergone breast reduction aappublications.org/content/135/3/584) strongly discourage cannabis use during lactation; the or breast implant surgery can breastfeed but should work closely chapter authors acknowledge evidence is limited and individualized care is important. with a lactation specialist because milk supply may be negatively c See the Centers for Disease Control and Prevention recommendations: “2009 H1N1 Flu (Swine Flu) impacted if ducts or nerves were severed during surgery. and Feeding Your Baby: What Parents Should Know” at http://www.cdc.gov/h1n1flu/infantfeeding .htm. Data from Kimberlin DW, Brady MT, Jackson MA, Long SS. Red book: 2015 report of the Committee Anatomy and Physiology of Lactation on Infectious Diseases. Elk Grove, IL: American Academy of Pediatrics, 2015; Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, Breast milk is produced by the mammary alveolar cells of the Centers for Disease Control and Prevention. Diseases and Conditions. When should a mother avoid breast after childbirth. The mammary gland is a highly evolved breastfeeding? http://www.cdc.gov/breastfeeding/disease; 2016; and Hill M, Reed K. Pregnancy, breast-feeding, and marijuana: a review article. Obstet Gynecol Surv. 2013;68:710–718. skin gland, and its rudiments are first seen during the sixth week in utero. Mammogenesis, or breast development, begins during puberty with increased breast size due mainly to estrogen and lobuloalveolar development facilitated predominantly by proges- terone. During pregnancy, with the support of these hormones Lactogenesis begins by midpregnancy, although actual milk and others, including prolactin and placental lactogen, breast secretion does not occur at this time because of high circulating levels glandular tissue further differentiates, and the alveolar epithelium of progesterone (and probably estrogen). During pregnancy, secretory proliferates and then becomes secretory. Research using ultrasound differentiation of the mammary epithelial cells into lactocytes that technology (Fig. 67.1) shows that the milk ducts branch close to have the ability to produce milk components occurs: this is known the nipple, that their number is lower and more variable than as lactogenesis I. At the end of gestation the alveoli are filled with previously believed, that most glandular tissue is close to the nipple, proteins, including sIgA, and leukocytes and desquamated cells: this and that the “lactiferous sinuses,” which were thought to store glandular fluid is colostrum. Lactogenesis II, or secretory activation milk, do not exist (Ramsay et al., 2005). These findings have of the lactocytes (also known as the milk coming in), usually occurs implications for hand expression of breast milk, since inadvertent between day 2 and day 8. This phase, defined by the copious onset pressure on the breast close to the nipple may actually inhibit milk of milk secretion, is triggered by birth and the drop in progesterone flow, as well as for breastfeeding after breast augmentation or level associated with removal of the placenta. Adequate circulating reduction surgery, since major nerves and milk ducts may have prolactin and cortisol levels are required, and other hormones, been unintentionally severed or damaged during surgery, with risk including insulin and thyroid hormone, likely play a supporting of reduced milk supply. role. During this time daily milk volume increases from about 50 to
1002 PART XI I I Nutrition OLD NEW 1. 2. 1. 3. 4. 2. 3. 4. • Fig. 67.1 Anatomy of the breast. (From Medela AG. Old vs new anatomy. (Available at http://www .medelabreastfeedingus.com/for-professionals/cbe-information/106/breast-anatomy-research.) 1-Ducts branch closer to nipple, 2-The conventionally described lactiferous sinuses do not exist, 3-Glandular tissue is found closer to the nipple, 4-Subcutaneous fat is minimal at the base of the nipple. 500 mL, and transitional milk is produced, a descriptor for milk that is literally transitioning in composition from colostrum to mature Arteriol milk (Neville, 1999; Neville et al., 2001; Pang and Hartman, 2007). Capillaries The control of lactogenesis is completely hormonal. Evidence suggests that milk removal or infant suckling is not needed for the programmed changes of lactogenesis, although milk removal may improve the efficiency of early milk secretion (Neville et al., 2001). Venule Delayed lactogenesis II has been associated with placental retention (failure of progesterone level to decline postpartum), hypothyroidism, a cesarean delivery, and premature delivery; there are also associations with factors related to glucose metabolism, including maternal Myoepithelial Milk cell insulin-dependent diabetes, elevated maternal BMI, and higher d infant birth weight (Nommsen-Rivers et al., 2012). If the mother begins to feed her infant at the breast (or to express PC milk from the breast), then the next phase of lactation, called galactopoiesis or maintenance of milk secretion, starts at approximately day 9 postpartum and continues until weaning and involution of Adipocytes the breast. The control of galactopoiesis is both endocrine and • Fig. 67.2 The milk secreting unit: the terminal duct lobular unit. a, autocrine. Prolactin and cortisol are necessary for milk production: Alveoli, d, ductule, PC, plasma cells. (From Neville MC. Milk secretion: an prolactin binds to epithelial cell receptors and is responsible for overview. Available at http://www.health-e-learning.com/articles/Neville_ activating the milk protein genes for α-lactalbumin and casein. MILK_SECRETION_2008.pdf.) Milk synthesis remains near 700 to 800 mL/day throughout lacta- tion, but the actual volume of milk is dependent on milk removal. With incomplete emptying of the breast because of infrequent or inefficient infant sucking, milk synthesis is adjusted downward activated, and afferent nerve endings send a signal to the central because of a locally produced whey protein called feedback inhibitor nervous system. The alveolar lactocytes are wrapped with myoepi- of lactation (FIL). FIL appears to act on alveolar cell receptors to thelial cells that lack innervation but have oxytocin receptors (Fig. decrease their sensitivity to prolactin and therefore to decrease milk 67.2). In the presence of oxytocin, they squeeze milk into the production. The cellular mechanisms for milk synthesis and secretion ducts, leading to milk ejection. Prolactin originates in the anterior are described elsewhere (Neville, 1999; Neville et al., 2001). pituitary, and although secretion is also stimulated by sucking, Milk that was accumulated in the alveoli cannot flow passively prolactin production is not inhibited by pain and stress like that into the ducts. Actual milk ejection, or galactokinesis, is dependent of oxytocin, and the milk ejection reflex, or “let down,” does not on the hormone oxytocin, which is produced in the posterior directly depend on it. pituitary. Oxytocin secretion is stimulated by infant suckling and During weaning or extended periods of infrequent sucking at other sensory inputs that mimic the infant such as cry, sight, smell, the breast, levels of prolactin drift downward. The tight junctions and touch. Stretch receptors in the canalicular ductal system are between alveolar lactocytes appear to open and allow passage of
CHAPTER 67 Breastfeeding 1003 electrolytes, including sodium and chloride. Elevated breast milk • BOX 67.3 Risk Factors for Lactation Failure sodium level is associated with several clinical situations, including or Difficulty involution and remodeling of the mammary gland, which occurs with cessation of milk secretion (Lawrence et al., 2016). Maternal Factors Maternal chronic illness (e.g., cystic fibrosis, diabetes type 1 or 2) Management of Breastfeeding Anatomic Prior breast surgery The management of lactation begins before pregnancy (AAP/ Inverted nipples, nipple size mismatch with infant mouth ACOG, 2012; ACOG, Optimizing Support for Breastfeeding, Tubular or variant breast shape (size per se is not a factor) Obesity 2016). Formal prenatal breastfeeding education (BFHI step 3), in History of breastfeeding difficulty addition to personalized information offered during prenatal visits, Perinatal complications (e.g., hemorrhage, hypertension/preeclampsia, shock, positively impacts exclusive breastfeeding and breastfeeding at 6 infection) months (Academy of Breastfeeding Medicine [ABM] Clinical Cesarean delivery Protocol 19, Breastfeeding Promotion in the Prenatal Setting, Multiples (twins, triplets, etc.) http://www.bfmed.org/Resources/Protocols.aspx; Lawrence et al., Mother–infant separation 2016). Ideally breastfeeding education, and the function of the Secondary—nipple trauma, nipple pain, engorgement mammary glands, should be taught in secondary school and continued throughout the reproductive life cycle. In support of Infant Factors this approach, maternal prenatal intention to breastfeed appears Premature delivery 7% below marized by the ABM Clinical Protocol 5, Peripartum Care, and birth weight, excessive pacifier use Clinical Protocol 7, Model Hospital Policy (http://www.bfmed.org/ Resources/Protocols.aspx), written hospital guidelines should promote and support breastfeeding for each mother–infant dyad per recommendations of the American Academy of Pediatrics and WHO, maximize each mother’s ability to meet her own first few hours after birth, (2) ability to transfer milk (or colostrum) breastfeeding goals, and maximize each infant’s opportunity to adequately at each feeding, (3) feeding at the breast 8 to 12 times receive full feeds of breast milk (BFHI step 1) (AAP, Breastfeed- per 24 hours as cued by infant hunger (rooting, fist sucking, ing and the use of Human Milk, 2012; Feldman-Winter et al., alerting), (4) nursing at both breasts each feeding for up to 15 to 2012; Sample Hospital Breastfeeding Policy for Newborns, 2016). 20 minutes per side or until there are signs of infant satiety (fewer The BFHI 10 steps serve as a useful and evidence-based guide to sucking bursts, longer pauses, sleepiness), and (5) the mother feeling hospital policy (Box 67.1). Each evidence-based step may require comfortable with the infant feeding at the breast. Maternal and changes in entrenched hospital routines that are not conducive infant risk factors for lactation difficulty (Box 67.3) should be to breastfeeding. For example, mothers should be encouraged identified within the first few hours after birth so that interventions to put the infant to breastfeed within the first hour after birth to promote maternal and infant health and the breastfeeding process (BFHI step 4). Newborns that are placed skin-to-skin on the can be promptly initiated, and this assessment process should be mother’s abdomen a few minutes after birth are able to initiate a ongoing throughout the hospital stay. “crawl” toward the breast and nipple, latch on, and begin sucking (http://www.breastcrawl.org/video.shtml). The necessary medical Latch On routines of infant identification, drying, warmth, assessment, and administration of prophylactic eye drops and vitamin K can be “Good latch” is the cornerstone of successful breastfeeding because safely delayed until after the first breastfeeding for healthy infants it permits adequate milk transfer to the infant and prevents nipple (AAP, Breastfeeding and the use of Human Milk, 2012). pain for the mother. Brief videos are available that demonstrate how to assist a mother achieve latch (Basics of Breastfeeding). Nursing at the breast is fundamentally different from bottlefeeding Initial Management in that the infant extracts the milk from behind the nipple while Normal healthy infants are able to latch on to the breast in the nursing rather than sucking on the nipple to elicit flow. There are first hour after birth. The goals for the infant during the postpartum several ways to hold an infant to breastfeed, but to achieve good stay include (1) achievement of latch on to the breast within the latch, the mother and infant should be tummy-to-tummy, regardless
1004 PART XI I I Nutrition of the holding position, with the infant facing the mother’s body Growth of the Breastfed Infant (AAP/ACOG, 2012). The mother can hold her breast well behind the areola using a “C hold” with four fingers under the nipple and The rate and pattern of weight gain of breastfed infants differs the thumb above. She then strokes the infant’s mid upper lip with from that of infants fed formula, and several studies have concluded her nipple, and once rooting is elicited and the infant opens its that the breastfed infant’s growth should be considered normative mouth, she can promptly bring the infant in so it takes in the (Butte et al., 1984b, 1990; Dewey et al., 1991, 1992). The WHO breast, including the areola, not just the nipple. The mother’s Multicentre Growth Reference Study was undertaken between nipple is protected since it is well back in the infant’s mouth, and 1997 and 2003 and gathered primary longitudinal growth data the infant’s jaw massages milk from behind the areola. The infant’s from about 8500 healthy and optimally breastfed children of nose and chin will contact the mother’s skin, and the mother differing ethnic, racial, and cultural backgrounds (Brazil, Ghana, should experience a tugging sensation without pain as the infant India, Norway, Oman, and the United States). WHO subsequently suckles with this deep latch. Many women acknowledge that published an international growth reference (http://www.who.int/ breastfeeding is initially painful because of challenges with establish- childgrowth/) based on the growth of these healthy and fully ing good latch and because of the uterine contractions elicited by breastfed infants that benchmarks growth and development from oxytocin during “let down,” but if breast or nipple pain persists, birth to age 5 years, replacing older references (de Onis et al., prompt breastfeeding assistance is needed. 2006). See the Centers for Disease Control and Prevention growth charts, which use the WHO standards (http://www.CDC.gov/ growthcharts/who_charts.htm). The First 2 Weeks to 2 Months Clinicians are occasionally in doubt as to when and how Each hospital should establish breastfeeding support groups or to intervene if a breastfed infant is not gaining adequate weight work with organized community support groups so that families (Powers, 2001). A newborn younger than 2 weeks must be evalu- have a resource on leaving the hospital (BFHI step 10). All breastfed ated if its weight is more than 10% below birth weight. A newborn infants should be seen by a knowledgeable healthcare professional who fails to regain birth weight by 2 weeks of age or is not at 3 to 5 days of age to recognize and to avoid potential problems gaining a minimum of 20 g per day should be evaluated. The of dehydration and severe jaundice (AAP, 2015). infant with growth faltering, when the weight for age (or weight The nursing history differs from infant to infant and over for length) is less than two standard deviations below the mean any 24-hour period, so although nursing 8 to 12 times per day or weight for age crosses more than two percentile channels is the average, some infants will “cluster feed,” nursing more downward on the growth chart, should also be evaluated. Infant frequently for short periods. Without anticipatory guidance, new physical examination and assessments of milk supply, intake, mothers may compare their infants with bottlefed infants and appropriateness of complementary foods, maternal history and misinterpret the normal frequency of breastfeeding to mean that behaviors, and the home environment are all part of the evaluation. they have insufficient milk. As infants get older, they nurse more Test weighing with an electronic scale before and immediately efficiently, and the frequency and duration of feedings decrease. after a feeding is one method of measuring milk intake (Meier New parents may expect their baby to cry when it is hungry and et al., 1990). Pumping after a feeding is a method to assess residual need guidance that crying is a late sign of hunger and can result milk. Causes of growth problems not specifically related to in an infant who is difficult to calm and latch. Earlier hunger breastfeeding must be considered, for example, cystic fibrosis or signs include rooting, finger and fist sucking, and lip smacking. cardiac disease in the infant or severe postpartum depression in Pacifier use is associated with a reduction in the risk of SIDS. the mother. However, pacifiers should not be introduced to breastfeeding infants until breastfeeding is well established, at about 3 to 4 Tongue Tie weeks of age, because frequent use of a pacifier can conceal hunger cues, and the offering of artificial nipples may interfere Tongue tie, or ankyloglossia, is a congenital disorder with a male with latch, both of which can adversely impact maternal milk predominance (3 : 1), found in 4%–16% of infants, in which there supply (Hauck et al., 2011; Task Force on Sudden Infant Death is a short lingual frenulum that may restrict tongue movement Syndrome, 2011). and impact function, including breastfeeding. Poor latch with Once lactogenesis stage II is completed (the “milk has come maternal nipple pain and insufficient milk transfer may result, in”), an infant who did not lose excessive weight and who is nursing although less than half of infants with even moderate to severe effectively should obtain enough milk to begin gaining weight, tongue tie appear to be affected (Ngerncham et al., 2013). As 15–30 g per day, by day 4 or 5. At this rate, most breastfed infants described in ABM Clinical Protocol 11, Neonatal Ankyloglossia will exceed their birth weight by 10 to 14 days and gain 20–30 g (http://www.bfmed.org/Resources/Protocols.aspx), standardized per day for the first 2 months. A breastfed infant who weighs less clinical tools to assess the degree of tongue tie and its impact on than birth weight at 2 weeks requires evaluation and intervention. breastfeeding include the Hazelbaker assessment tool for lingual Anticipatory guidance should include information about growth frenulum function (Amir et al., 2006). One-week prefrenotomy spurts, in which infants are restless and breastfeed more often than and postfrenotomy changes in sucking pattern and milk transfer usual for 2 to 3 days. These typically occur at approximately ages were demonstrated on submental ultrasonography (Geddes et al., 10 days, 3 weeks, 6 weeks, 3 months, and every few months and 2008); however, whether or not frenulotomy (division of the may be exhausting for the mother. Since milk supply depends on frenulum), frenulectomy (removal of the frenulum), or frenuloplasty infant demand, permitting the infant to breastfeed frequently is (frenulotomy with stitches) clearly improves breastfeeding has been optimal. In addition, screening for maternal depression, which is controversial. Systematic reviews including five randomized con- associated with a decreased duration of breastfeeding, and for other trolled studies, of which four used validated measures of latch as maternal concerns, such as sore nipples, is critical (AAP/ACOG, a primary outcome, concluded that frenotomy in selected infants 2012; Dias and Figueiredo, 2015). appears to provide objective improvements in breastfeeding
CHAPTER 67 Breastfeeding 1005 measures, with subjective improvement in maternal pain (Brooks mild discomfort is common, but severe nipple pain, the presence et al., 2014; Francis and Krishnaswami, 2015). of cracks or bruises, discomfort that continues throughout a feeding, or pain that is not reducing by the end of the first 2 weeks is not normal. The most common cause of nipple pain is difficulty with Breastfeeding the Late Preterm Infant breastfeeding technique, specifically improper latch, and prompt Late preterm infants (34–36 6 7 weeks’ gestation) are at high risk of skilled help is the primary intervention. Limited milk transfer complications of insufficient breast milk intake, including dehydra- occurs when the infant is attached incorrectly, resulting in poor tion, hypernatremia, severe jaundice, and poor weight gain, and infant weight gain and impaired milk production. Other potential their mothers are at high risk of lactation failure due to immature causes of nipple pain include overzealous breast cleansing, use of and ineffective infant sucking, as reviewed in ABM Clinical Protocol preparations that irritate the skin, skin trauma leading to impetigo, 10, Breastfeeding the Late Preterm Infant (http://www.bfmed.org/ Candida infection, and rarely dermatologic conditions. Treatment Resources/Protocols.aspx) (Raju, 2006; Meier et al., 2013). Within for nipple pain depends on the underlying cause. If severe trauma hours of birth the mother can be taught to hand express colostrum exists, it may be necessary either to express milk or use a nipple to feed the baby, and within 24 hours of birth she can express breast shield with guidance from a lactation specialist until the nipple milk every 2 to 3 hours after breastfeeding using a hospital-grade has healed; other therapies are not evidence based (Dennis et al., electric pump. Infant interventions include waking the infant to feed 2014). Ultrathin nipple shields may also help the infant latch on and providing supplementation with or after each feeding at least to inverted, flat, or engorged nipples, may reduce rapid milk flow, every 2 to 3 hours with expressed colostrum or breast milk (mixed may facilitate milk transfer for premature infants, and may support with formula if there is not yet enough breast milk). This “trio” of the transition back to the breast for bottlefed infants. nursing at the breast, followed by supplementation (or simultaneous if a supplemental nursing system is used) and then maternal milk Engorgement and Blocked Ducts expression, forms “triple feeds,” a bridge to successful lactation for the at-risk mother–infant dyad. In this manner the mother’s Physiologic breast fullness occurs because of vascular congestion milk supply is not at risk or diminished because of ineffective or during lactogenesis II. Pathologic engorgement, in which the infant infrequent sucking, and the physiologically immature infant is cannot initially remove milk, is the firm, diffuse, and painful guaranteed sufficient intake. A breastfeeding management plan overfilling and edema of breasts usually caused by rapid increase should be established before discharge. in milk volume or a skipped feeding. As described in ABM Clinical Protocol 20, Engorgement (http://www.bfmed.org/Resources/ Breastfeeding the Very Low Birth Weight Protocols.aspx), the best treatments for engorgement are a warm shower and gentle hand massage to soften the areola and permit Premature Infant the infant to attach and frequent effective breastfeeding (or hand Mothers of VLBW and premature infants face multiple barriers milk expression if the infant is not able to breastfeed) followed by to breastfeeding, including potentially incomplete mammary gland cool packs for 5 minutes after each feeding. “Reverse pressure growth and inadequate priming of the mammary epithelium, softening,” a simple technique in which gentle pressure pushes mother–infant separation, infant fragility, the need to maintain fluid backward and upward in the breast to reduce areolar edema milk supply by milk expression for weeks to months, and fatigue and permit latch, may also be effective (Cotterman, 2011). Engorge- and stress, which may inhibit lactation (Jones and Spencer, 2007). ment should not be confused with a plugged milk duct, which Mothers can be encouraged to begin milk expression shortly after can result in a localized lump in one area of the breast, usually delivery and maintain a pumping frequency of eight times per day because of infrequent or ineffective feedings or local pressure because to optimize and maintain milk production (Furman and Minich, of constrictive clothing. Treatment includes warm packs, gentle 2002; Jones and Spencer, 2007). Milk volume on day 4 may be massage from the painful area toward the nipple, frequent effective predictive of supply at 6 weeks (Hill et al., 1999); those who feedings using different infant positions to facilitate emptying, and combine massage or hand expression (“hands-on pumping”) with discontinuation of tight or underwire bras. use of a double electric breast pump can exceed term milk volumes and may increase the caloric density of their milk (Jones et al., Mastitis 2001; Morton et al., 2009, 2012). Lactation counseling does not increase maternal stress and anxiety and can increase the number As a single area of localized warmth, tenderness, edema, and of mothers who initiate lactation and the volume of breast milk erythema in one breast more than 10 days after delivery, mastitis their infants receive (Sisk et al., 2006). Multifaceted approaches may present with a sudden onset of breast pain, myalgia, and fever to lactation support, including education of staff and parents, or with flulike symptoms. The infection commonly enters through skin-to-skin (kangaroo) care, supportive hospital policies, peer a break in the skin, usually a cracked nipple; however, milk stasis support groups with transportation assistance, access to breast from engorgement or obstruction from plugged ducts can also pumps, and lactation consultant availability, have all been dem- lead to mastitis. As reviewed in ABM Protocol 4, Mastitis (http:// onstrated to increase rates of breast milk provision for VLBW www.bfmed.org/Resources/Protocols.aspx), treatment includes infants (Meier et al., 2004; Dereddy et al., 2015). antibiotics and continuation of breastfeeding with frequent feeding (or pumping) to allow drainage. Additional therapy includes good fluid intake, bed rest, and pain control. Maternal Breastfeeding Issues Nipple Pain Low Milk Supply Sore nipples and pain are the most common complaints of Actual low milk supply most often results from infrequent and/ breastfeeding mothers in the immediate postpartum period. Early, or ineffective feedings at the breast, introduction of formula
1006 PART XI I I Nutrition supplementation, which decreases breastfeeding frequency, or early • BOX 67.4 US Medical Eligibility Criteria for (before 3 weeks) introduction of bottlefeeding, each of which Contraceptive Use can decrease milk supply because of inadequate milk removal. Primary treatment includes increased effectiveness and frequency MEC 1 No restriction (method can be used) of milk removal; galactogogues such as fenugreek (although not MEC 2 Advantages generally outweight theoretical or proven risks evidence based) may be helpful if use is temporary and supervised MEC 3 Theoretical or proven risks usually outweight the advantages (Mortel and Mehta, 2013); ABM Clinical Protocol 9, Galactogogues MEC 4 Unaccepatable health risk (method not be usde) (http://www.bfmed.org/Resources/Protocols.aspx), provides an From Centers for Disease Control and Prevention. U.S. medical eligibility criteria for contraceptive additional summary. Maternal factors that reduce milk supply use, 2010: adapted from the World Health Organization Medical Eligibility Criteria for Contraceptive include primary or secondary hypoprolactinemia, absence of an Use, 4th edition. MMWR Morb Mortal Wkly Rep. 2010;59(RR04):1–85. intact adenohypophyseal axis, severe maternal illness, including sepsis or hemorrhage, prior breast surgery, use of estrogen-containing contraceptives, and severe fatigue, stress, or pain. It is not clear if maternal smoking actually reduces milk supply or is a behavioral Maternal Employment Outside the Home risk factor for decreased duration of breastfeeding. Perceived low milk supply, in which the infant has a normal growth pattern but Mothers who seek to combine breastfeeding and bottlefeeding the mother believes she does not have sufficient milk, can result or who face returning to work can offer one bottle of expressed from growth spurts leading to increased infant demand, changes milk daily from the time breastfeeding is established at 2 to 3 in the efficiency of the breast around 4 weeks leading to decreased weeks of age: clinicians and mothers report that newborns who apparent fullness before nursing, or increased efficiency of infant are unaccustomed to a bottle may refuse one if it is not introduced nursing beginning at 2 to 3 months leading to less frequent or before 1 month of age. Although exclusive breastfeeding through shorter breastfeeding sessions. Infant weight check is diagnostic. 6 months with addition of complementary feeds and continued Maternal depression may also contribute to maternal perception breastfeeding until 1 to 2 years of age is an evidence-based of low milk supply and is associated with early cessation of medical recommendation, mothers may face personal and work breastfeeding, so screening and treatment are essential (Dias and constraints. Health insurance plans now must cover the cost of a Figueiredo, 2015). breast pump (Healthcare.gov, 2016). Although a double electric pump is considered the “gold standard” for optimal milk expres- sion, a recent review found that low-cost interventions, including Contraception hand expression, breast warming, and relaxation tapes, may be The lactational amenorrhea method (LAM) is considered a suf- as or more effective in specific situations (Becker et al., 2015). ficient criterion for “how to be reasonably sure a woman is not Supportive nonjudgmental information about flexible ways to pregnant,” a formal endorsement of its contraceptive efficacy combine working outside the home with breastfeeding should (Centers for Disease Control and Prevention, 2013) (Box 67.4). be offered. In addition to expressing and storing breast milk, LAM and nonhormonal or barrier methods of contraception do mothers may want to identify reduced or flexible hours, take the not impact breast milk supply and are recommended if acceptable infant to work, or breastfeed during breaks at a nearby childcare to the mother and her partner. For breastfeeding mothers, according facility; working 19 hours or less per week was associated with to the US Medical Eligibility Criteria (MEC 1-4) grading system, a higher likelihood of continued breastfeeding regardless of the intrauterine devices (IUDs), progestin-only contraceptive pills, duration of maternity leave (Li et al., 2008; Galtry, 2015; Xiang implants (etonogestrel), and injectables (depot medroxyprogesterone et al., 2016). acetate [DMPA]) are classified as MEC2 for use from 10 minutes after placental delivery to 1 month postpartum and MEC1 for Jaundice and Breastfeeding use 1 month or more postpartum. The use of combined oral contraceptives (COCs) is contraindicated less than 21 days “Breast-nonfeeding jaundice” and “breast milk jaundice” are distinct postpartum (MEC 3) (Centers for Disease Control and Prevention, clinical entities, with differing approaches (Academy of Breastfeeding 2013). Although the US Selected Practice Recommendations for medicine protocol Committee, ABM Clinical Protocol 22, Jaundice, Contraceptive Use, 2013, provides guidance to health providers, http://www.bfmed.org/Resources/Protocols.aspx; Preer and Philipp, evidence is incomplete regarding the impact of hormonal methods 2011). on milk supply. A recent systematic review on this topic concluded that evidence was limited and conflicting and that the trials Breast-Nonfeeding Jaundice were of moderate to low quality: two of eight trials found a negative effect on breastfeeding duration (of COCs vs placebo and hormonal Severe jaundice is the most frequent reason for readmission of late vs nonhormonal IUDs), and two of six trials found lower preterm and term infants, most of whom are breastfeeding. If there milk volume (with COCs vs placebo) (Lopez et al., 2015). A is any delay in lactogenesis II or if the infant has ineffective milk review focused on progestin-only contraception generally did not removal or infrequent sucking, less milk will be ingested and show an adverse impact on breastfeeding outcomes; however, consequently less milk will be produced, leading to a cycle of evidence regarding the effect of early postpartum DMPA is decreased demand and decreased supply, with consequent “starvation methodologically weak (Brownell et al., 2012; Phillips et al., 2016.) jaundice” or breast-nonfeeding jaundice. The most common risk Centers for Disease Control and Prevention guidelines (http:// factor for inadequate milk removal is late preterm birth. The neonatal www.cdc.gov/reproductivehealth/unintendedpregnancy/usmec.htm) intestine has highly active glucuronidases, which cleave conjugated and ABM Clinical Protocol 13, Contraception and Breastfeeding bilirubin to unconjugated bilirubin. The unconjugated bilirubin (www.bfmed.org/Resources/Protocols.aspx), offer additional is readily reabsorbed and recirculated to the liver for conjugation. detail. Milk alleviates bilirubin recirculation by providing calories and
CHAPTER 67 Breastfeeding 1007 gastrocolic stimulation. Thus treatment focuses on improving 2013). When frozen appropriately, milk can be stored for as long maternal lactation and providing milk (preferably expressed or as 6 months. Milk should never be thawed in a microwave oven, donor human milk or formula) to the infant. Phototherapy should should be used within 24 hours, and should not be refrozen (Centers be initiated as per guidelines (Academy of Breastfeeding Medicine for Disease Control and Prevention, 2016). Protocol Committee, 2010). Reports from the US Pilot Kernicterus Registry note that more Donor Human Milk than 90% of cases of kernicterus have been in breastfed infants, with late preterm infants and those with glucose 6-phosphate Donor milk generally refers to milk donated to a milk bank by a dehydrogenase (G6PD) deficiency overrepresented (Johnson, 2009). mother with excess supply, usually a woman who delivers a term Primary prevention includes establishment of optimal lactation infant and generally later in lactation. After rigorous screening and measurement of total serum bilirubin concentrations at dis- processes, the milk is heat treated at 62.5°C for 30 minutes, the charge and at the 3- to 5-day follow-up visit (AAP 2015). Guidelines , Holder pasteurization method. Donor milk is used primarily in for families and providers are now also available (http://www.cdc.gov/ NICUs to support the feeding of preterm neonates whose mothers ncbddd/jaundice/index.html). have inadequate milk production to meet their neonates’ needs (Arslanoglu et al., 2013). The Human Milk Banking Association of North America is a nonprofit entity founded in 1985 that has Breast Milk Jaundice set guidelines for collection and pasteurization of milk and for use In breastfed infants, total serum bilirubin concentrations remain in NICUs. In 2016 there were 18 Human Milk Banking Association elevated, and in a few infants this may last as long as 12 weeks. of North America milk banks in the United States and Canada In formula-fed infants, serum bilirubin concentration declines, (https://www.hmbana.org/). reaching values of less than 1.5 mg/dL by the 11th or 12th day The Holder pasteurization process results in a milk that is free after birth. It has been suggested that elevation in serum bilirubin of microbial contamination, but biologically and immunologically concentration may be protective against oxidative injury since active factors may be affected adversely, including immunoglobulins, bilirubin has been shown to be an effective antioxidant in vitro. lactoferrin, lysozyme, erythropoietin, lipase, and insulin. The heat Infants with breastfeeding jaundice appear healthy and, other than treatment does not affect oligosaccharides (which may be active in jaundice, have completely normal physical examination findings preventing NEC) (Ewaschuk et al., 2011; Arslanoglu et al., 2013). and are growing normally. Mature human milk contains an The donor milk carbohydrate content is generally preserved, but unidentified factor that enhances the intestinal absorption of bili- protein content may be low because milk is donated later in lactation rubin in a susceptible host infant to produce jaundice. As the from term mothers. The fat content of donor milk is also low production of the factor diminishes over time and the liver matures, because milk is not homogenized, and there are multiple transfers the serum bilirubin concentration eventually returns to normal. of the milk with loss of fat at each step (García-Lara et al., 2013). A direct bilirubin level should be measured to exclude biliary Clinical studies on the use of donor human milk as compared atresia, liver disease, sepsis, and other conditions, and an evaluation with formula in the NICU suggest that it supports lower rates of should exclude other causes of prolonged unconjugated hyperbili- NEC and better feeding tolerance but poorer growth and more rubinemia such as galactosemia, hypothyroidism, urinary tract biochemical abnormalities in nutritional status (Boyd et al., 2007; infection, pyloric stenosis, or low-grade hemolysis due to G6PD Quigley and McGuire, 2014). A randomized trial of donor milk or other causes. Parents should be reassured, since there is no harm versus preterm formula as supplements for inadequate volumes of to the infant, and breastfeeding should not be interrupted unless the mother’s own milk was conducted in preterm infants (Schanler the bilirubin level rises to reach phototherapy level (>20 mg/dL) et al., 2005). That appropriate matched study found no difference (Preer and Philipp, 2011). in the major outcome of NEC and/or late-onset sepsis between study groups. A parallel group that continued to receive only their Collection and Storage of Human Milk mother’s milk had significantly lower rates of these outcomes (Sullivan et al., 2010). The human milk groups in that study, Electric breast pumps enable optimal milk production for mothers however, also received bovine-based milk products containing intact separated, either by employment or hospitalization, from their bovine protein. An exclusive human milk diet, appropriately fortified infant. General techniques for ensuring cleanliness during milk with a human milk–derived fortifier, resulted in markedly lower expression begin with good hand washing with soap and water; rates of NEC and surgery for NEC, fewer parenteral nutrition collection kits should be rinsed, cleaned with hot soapy water, and days, and lower mortality compared with a diet containing intact air dried. Bacteriologic testing is generally not necessary for milk bovine milk fortifier and/or formula (Sullivan et al., 2010; Cristofalo collected for feeding to a mother’s own infant. Milk can remain et al., 2013; Abrams et al., 2014). Thus donor milk is an alternative unrefrigerated for 6 to 8 hours, in an insulated cooler bag for 24 to the mother’s own milk but not a replacement for it. Furthermore, hours, and in a refrigerator for 5 days, each without significant a recent report showing that use of donor milk was associated with bacterial proliferation (Centers for Disease Control and Prevention, increasing use of mother’s own milk suggests that use of donor 2016; Academy of Breastfeeding Medicine Protocol Committee, milk may serve as a bridge to use of mother’s own milk (Kantorowska 2010). As described in ABM Clinical Protocol 8, Human Milk et al., 2016). Storage (www.bfmed.org/Resources/Protocols.aspx), freezing is the The business of donor milk purchase by hospitals (and individuals) preferred method of storing milk that will not be fed: single milk has created an industry of for-profit human milk banking (Prolacta expressions should be packaged separately and labeled with the Bioscience Monrovia, CA and Medolac Laboratories Lake Oswego, date (and the name of the infant if for center or hospital use). OR) that relies on paid donors: political and social issues include Unlike heat treatment, freezing preserves many of the nutritional concern for diversion of milk from nonprofit banks. Milk selling and and immunologic benefits of human milk, and pasteurization of sharing over the Internet for personal use has become a relatively the mother’s own milk offers no additional benefit (Cossey et al., common practice outside medical venues; however, evidence regarding
1008 PART XI I I Nutrition spoilage, impurity (mixing with bovine milk), and contamination Schanler RS, Krebs N, Mass S, eds. AAP/ACOG Breastfeeding Handbook (infectious agents, caffeine, smoke exposure) is very discouraging, for Physicians. Elk Grove: American Academy of Pediatrics; 2013. and the Food and Drug Administration advises against this practice Sinha B, Chowdhury R, Sankar MJ, et al. Interventions to improve (http://www.fda.gov/ScienceResearch/SpecialTopics/Pediatric breastfeeding outcomes: a systematic review and meta-analysis. Acta Paediatr Suppl. 2015;104:114-134. TherapeuticsResearch/ucm235203.htm; Geraghty et al., 2011; Keim Thulier D. Weighing the facts: a systematic review of expected patterns et al., 2015). of weight loss in full-term, breastfed infants. J Hum Lact. 2016;32: 28-34. Conclusion In summary, evidence is compelling that breastfeeding significantly Suggested Educational Resources reduces all-cause mortality and the number and severity of infec- on the Web tions in term and preterm infants in developed and developing countries. Strong evidence demonstrates that breastfeeding also This list is neither exhaustive nor presented in a specific order but is intended promotes maternal health. Breastfeeding is also likely associated as an introduction to Web-based educational materials that promote with long-term beneficial effects on infant health, growth, and or inform about breastfeeding. All listed resources were cost-free at the time of this publication. development. Substantial increases are needed in the rates of Academy of Breastfeeding Medicine has clinical protocols related to breastfeeding, particularly among racial, ethnic, and socioeco- breastfeeding, which are not intended as standards of care but offer nomic subpopulations that have the highest infant morbidity and informative guidelines. These are available at http://www.guideline.gov mortality rates. Healthcare practitioners are uniquely positioned and at http://www.bfmed.org/Resources/Protocols.aspx. to influence women in their decision to breastfeed and should American Academy of Pediatrics has created The Breastfeeding Residency not only collaborate with lactation specialists but should also be Curriculum Online Resource for program directors and other faculty. prepared to assist in the management of breastfeeding problems This resource offers “tools and resources about breastfeeding including themselves. Discussion regarding the benefits of breastfeeding and clinical and cultural cases, prepared presentations about breastfeeding the risks of formula permit the mother to make an informed management, and evaluation and tracking tools” and is available at infant feeding choice, and for many women, physician support http://www2.aap.org/breastfeeding/curriculum/. Baby-Friendly USA Inc. is the official body for the Baby-Friendly Hos- is critical. pital Initiative in the United States. The website https://www.baby friendlyusa.org/ is an entry point for beginning work toward designation. Suggested Readings Expanding Clinicians’ Roles in Breastfeeding Support is a two-part online tutorial that provides 3 hours of content material that is compatible American College of Obstetricians and Gynecologists’ Committee on with the Baby-Friendly Hospital Initiative and serves to meet physician Obstetric Practice; Breastfeeding Expert Work Group. Optimizing education requirements for Baby-Friendly Hospital Initiative certifica- support for breastfeeding as part of obstetric practice. ACOG Committee tion: http://www.hriainstitute.org/breastfeedingcme/. The Stanford opinion no. 658. Obstet Gynecol. 2016;127:e86-e92. School of Medicine, Newborn Nursery at Lucile Packard Children’s Department of Health and Human Services. The Surgeon General’s Hospital website “is designed to support the educational goals of Call to Action to Support Breastfeeding. US Department of Health our pediatric trainees” and is a resource for all healthcare providers and Human Services, Office of the Surgeon General; 2011. promoting breastfeeding. Multiple video clips are included: http:// https://www.surgeongeneral.gov/library/calls/breastfeeding/calltoac- newborns.stanford.edu/Breastfeeding/. tiontosupportbreastfeeding.pdf. LactMed is a database with information on the safe use of medications Gartner LM, Morton J, Lawrence RA, et al. Breastfeeding and the use during lactation and is located on the National Library of Medicine’s of human milk. Pediatrics. 2005;115:496-506. ToxNet at http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT. Grummer-Strawn L, Rollins N. Summarizing the health effects of LaLeche League is an international organization dedicated to providing breastfeeding. Acta Paediatr. 2015;104:1-2. information and support to breastfeeding mothers: http://www.llli.org/. Ip S, Chung M, Raman G, et al. Breastfeeding and maternal and infant Wellstart International’s Lactation Management Self-Study Modules Level health outcomes in developed countries. Evid Rep Technol Assess (Full 1 (4th ed) is an educational tool with clinical cases in a question– Rep). 2007;153:1-186. answer format and is intended for health professionals interested in Kramer MS, Chalmers B, Hodnett ED, et al. Promotion of Breastfeeding breastfeeding. The link http://www.wellstart.org provides access to a Intervention Trial (PROBIT): a randomized trial in the Republic of free download for the first three modules, with a webpage of links to Belarus. JAMA. 2001;413-420. promote breastfeeding at http://www.wellstart.org/links.html. Morrow AL, Chantry CJ. Breastfeeding updates for the pediatrician. Preface. Pediatr Clin North Am. 2013;60(1):xv-xvii. Preer GL, Phillip BL. Understanding and managing breast milk jaundice. Complete references used in this text can be found online at www Arch Dis Child Fetal Neonatal Ed. 2011;96:F461-F466. .expertconsult.com
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