TNU Journal of Science and Technology
230(01): 169 - 176
http://jst.tnu.edu.vn 169 Email: jst@tnu.edu.vn
THE FIRST 1000 DAYS AND STUNTING: A CASE-CONTROL STUDY OF
4,054 CHILDREN AGED 24-72 MONTHS IN HOAN KIEM DISTRICT, HANOI
Le Thi Tuyet*, Nguyen Dung Nhi
Hanoi National University of Education
ARTICLE INFO
ABSTRACT
Received:
23/7/2024
Identifying characteristics in the first 1,000 days of life that affect
stunting is crucial for early prevention of stunting in children. This study
aims to determine the association between pregnancy, childbirth, and
child care with stunting in preschool children in the Old Quarter of
Hanoi. A case-control study was conducted on 4,054 children aged 24-
72 months in Hoan Kiem district. Stunted children (n=393) and children
with normal height (n=3,661) were classified according to WHO
standards with a height-for-age Z-score threshold of -2 SD. Logistic
regression analysis (adjusted for age and gender) showed that factors
affecting stunting include: father's age under 22 (OR=1.71), infants born
before 36 weeks (OR=1.54), cesarean section (OR=1.23), forceps
delivery (OR=2.29), birth weight under 2.8 kg (OR=1.43), and formula
feeding during the first 6 months (OR=1.27), weaning before 5 months
(OR=1.59) and weaning after 7 months (OR=1.43). However, mother's
age, pregnancy stress, maternal weight gain during pregnancy, and
breastfeeding duration were not statistically significantly related to
stunting. The study results suggest that encouraging natural delivery,
exclusive breastfeeding in the first 6 months, and introducing solid foods
in the sixth month are effective strategies for preventing stunting during
the first 1,000 days.
Revised:
17/10/2024
Published:
18/10/2024
KEYWORDS
Childcare
Delivery modes
First 1,000 days of life
Stunting
Hanoi preschool
1000 NGÀY ĐẦU ĐỜI VÀ THẤP CÒI: MỘT NGHIÊN CỨU BỆNH-CHỨNG
TRÊN 4.054 TRẺ 24 - 72 THÁNG TUỔI TẠI QUẬN HOÀN KIẾM, HÀ NỘI
Lê Thị Tuyết*, Nguyễn Dung Nhi
Trường Đại học Sư phạm Hà Nội
TÓM TẮT
Ngày nhận bài:
23/7/2024
Xác định các đặc điểm trong 1.000 ngày đầu đời ảnh hưởng đến thấp còi
rất quan trọng để phòng ngừa thấp còi sớm ở trẻ. Nghiên cứu này nhằm xác
định mối liên hệ giữa thai kỳ, sinh nở và chăm sóc trẻ với tình trạng thấp
còi ở trẻ mầm non phố cổ Hà Nội. Nghiên cứu bệnh chứng thực hiện trên
4,054 trẻ từ 24-72 tháng tuổi tại quận Hoàn Kiếm. Trẻ thấp còi (n=393) và
trẻ có chiều cao bình thường (n=3.661) được phân loại theo tiêu chuẩn
WHO với ngưỡng Z-score chiều cao theo tuổi là -2 SD. Phân tích hồi quy
logistic (điều chỉnh tuổi và giới tính) cho thấy các yếu tố ảnh hưởng đến
thấp còi gồm: tuổi cha dưới 22 (OR=1,71), trẻ sinh trước 36 tuần thai
(OR=1,54), sinh mổ (OR=1,23), sinh bằng forceps (OR=2,29), cân nặng
khi sinh dưới 2,8 kg (OR=1,43), uống sữa công thức trong 6 tháng đầu
(OR=1,27), ăn dặm ở 5 tháng (OR=1,59) và sau 7 tháng (OR=1,43). Tuy
nhiên, tuổi mẹ, stress thai kỳ, tăng cân của mẹ trong thai kỳ, thời gian bú
sữa mẹ không có liên quan ý nghĩa thống kê với thấp còi. Kết quả nghiên
cứu đề xuất khuyến khích sinh thường, bú mẹ hoàn toàn trong 6 tháng đầu
và ăn dặm vào tháng thứ 6 là các chiến lược hiệu quả để phòng ngừa thấp
còi ở trẻ.
Ngày hoàn thiện:
17/10/2024
Ngày đăng:
18/10/2024
DOI: https://doi.org/10.34238/tnu-jst.10805
* Corresponding author. Email: tuyetlt@hnue.edu.vn or lttuyet@gmail.com
TNU Journal of Science and Technology
230(01): 169 - 176
http://jst.tnu.edu.vn 170 Email: jst@tnu.edu.vn
1. Introduction
The first 1000 days of life span from conception to a child's second birthday. This period is
crucial for rapid growth and development, and any nutritional imbalances during this time can lead
to lasting health issues [1]. Inadequate care and nutrition for mothers during pregnancy and
children after birth can result in prolonged malnutrition in children, potentially leading to stunted
growth in the future [2].
Stunting, characterized by a child's low height for their age, is often a result of malnutrition and
recurrent infections. Stunting is a major public health issue, with many children experiencing
moderate to severe forms. According to the 2018 Global Nutrition Report, 150.8 million children
under the age of five (22.2%) are stunted [3]. In Vietnam, despite a significant reduction in the rate
of stunted children, it remains high. A 2015 survey reported that 21.4% of children aged 2-5 years
across the country were stunted [4], while a 2019 survey found an 11.5% stunting rate among Kinh
children in some northern provinces [5]. Moreover, stunting diminishes future labor capacity,
thereby impacting economic development. Research into the factors affecting stunting is crucial as
it informs the development of timely policies and interventions to reduce stunting rates, thereby
improving the nation's health and future labor productivity [6], [7].
The first 1000 days of life can be identified in four distinct stages: nine months to birth:
pregnancy; birth to six months: breastfeeding; six to 12 months: introduction of solid foods; and
beyond 12 months: transition to a family diet [2]. Each stage affects the growth and development
of children, including their height. Various characteristics during pregnancy and early care of
children have been shown to be related to the risk of stunting [8], [9]. However, these
characteristics vary by region and ethnicity [10], [11]. Therefore, the objective of this study is to
investigate the influence of some characteristics of the first 1000 days of life on stunting in children
in Hoan Kiem district - an old quarter district of Hanoi, Vietnam. The results of the study provide
data for giving recommendations in the way of caring for and nurturing children during the first
1,000 days of life, helping the children achieve optimal height and physical strength in the future.
2. Material and Methods
2.1. Study design and participants
A case-control study was derived from a cross-sectional study, which conducted from January
2018 to June 2019 in 18 public kindergartens in Hoan Kiem district, Hanoi, Vietnam. The case
group included stunted children, and the control group included children with normal height.
Participants were preschool children aged 24-72 months. Exclusions included those absent on
surveillance day or with acute or chronic diseases like tuberculosis, HIV, or kyphosis scoliosis.
Anthropometric measurements were taken for 4,615 children, and parents completed a
questionnaire about pregnancy, childbirth, and early childcare. Responses covering the first 1,000
days of life were obtained for 4,054 children.
The formula for calculating the sample size for the case group in a case-control study derived
from a cross-sectional study is as follows:
n = 𝑍2 × 𝑃 × (1 − 𝑃)
𝐸2
(n: The required sample size for the case group; Z: The Z-score corresponding to the desired
level of statistical significance (typically, Z = 1.96 for a 5% significance level); P: The estimated
proportion of the event in the population (the prevalence of the condition in the cross-sectional
study); E: The desired level of precision (acceptable margin of error)).
In this study, we calculated the sample size using the following parameters: Z = 1.96, P = 0.10
[5], and E = 0.05, resulting in an estimated sample size of approximately 139 for the case group.
Accordingly, the inclusion of 393 stunted children and 3661 children with normal height from the
cross-sectional study satisfies the required sample size for the case-control study.
TNU Journal of Science and Technology
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2.2. Collection of Anthropometric Data
Anthropometric measurements were taken in the morning in a climate-controlled room.
Children in light clothing were weighed with an electronic scale (accuracy: 100 grams) and
measured for height with a stadiometer (accuracy: 0.1 cm) following WHO guidelines.
2.3. Classification of Nutritional Status
For children under 60 months, the 2006 World Health Organization (WHO) criteria were used
to determine the weight-for-age Z-score (WAZ), height-for-age Z-score (HAZ), BMI-for-age Z-
score (BAZ), and weight-for-height Z-score (WHZ) 6. For those over 60 months, 2007 WHO
criteria were used. Analyses used WHO Anthro software (version 3.2.2) for under-60 months and
AnthroPlus® (version 1.0.4) for over-60 months 7. Stunting was classified as HAZ<-2SD.
2.4. Data Analysis
Quantitative variables were presented as mean ± SD if normally distributed or median (25th–
75th percentile) if not. The Student’s t-test compared normal distributions, while the Mann-
Whitney U test compared non-normal ones. Proportional differences were analyzed using the Chi-
square test. Binary logistic regression examined risk factors for stunting. A p-value < 0.05 was
considered significant.
2.5. Research ethics
This study received approval from the Ethical Committee in Biomedical Research of the
National Institute of Nutrition (Decision No. 343/VDD-QLKH). Parents of all participating
children were thoroughly informed about the study's objectives and contents, and signed informed
consent forms after receiving complete information.
3. Results and Discussion
3.1. Result
3.1.1. Characteristics of the study subjects
Table 1 shows the sex ratio, age group ratio, age, weight, height, BMI, WAZ, HAZ, BAZ, and
WHZ of children in the case and control groups.
Table 1. Anthropometric characteristics of the study subjects
Indices
Normal group (n=3,661)
Stunted group (n =393)
p-value
Sex
(n,%)a
Male
1928 (90.1%)
231 (9.9%)
0.562
Female
1733 (90.6%)
180 (9.4%)
Age
group
(n,%)a
months
24.0 – 35.9
593 (87.2%)
87 (12.8%)
< 0.0001
36.0 – 47.9
820 (88.9%)
102 (11.1%)
48.0 – 59.9
1503 (90.5%)
157 (9.5%)
60-71.9
745 (94.1%)
47 (5.9%)
Age (month)b
48.4 (38.1 – 58.6)
46.0 (35.8 – 59.2)
0.003
Weight (kg)b
15.5 (13.8 – 18.0)
12.9 (11.7 – 14.0)
< 0.0001
Height (cm)b
101.0 (96.0 – 106.0)
90 (86.0 – 94.3)
< 0.0001
BMI (kg/m2)b
15.4 (14.4 – 16.7)
15.5 (14.6 – 17.1)
0.581
WAZb
-0.14 (-0.86 –0.72)
-1.68 (-2.3 – -1.01)
< 0.0001
HAZb
-0.35 (-1.06 – 0.37)
-2.5 (-3.1 – -2.2)
< 0.0001
BAZb
0.04 (-0.72 – 0.90)
0.11 (-0.6 – 1.17)
0.721
WHZb
0.02 (-0.75 – 0.90)
-0.18 (-0.89 – 0.84)
0.061
aVariables are expressed as n, % of the total study population; p-values were obtained from the Chi-square test.
bVariables are expressed as median (25th-75th percentile); p-values were obtained from the Mann-Whitney U test
No differences were found in sex ratio, BMI, BAZ, and WHZ between normal and stunted
groups. Stunting rates decreased with age: 12.8% (24 – 35.9 months), 9.5% (48 – 60 months), and
TNU Journal of Science and Technology
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5.9% (60 – 72 months). Weight, height, WHZ, and HAZ were significantly lower in the stunted
group (p-value < 0.05).
3.1.2. Associations between characteristics of pregnancy, childbirth, and stunting in children
Table 2 shows the relationship between pregnancy and childbirth characteristics and stunting
among preschool children in Hoan Kiem, Hanoi.
Table 2. Binary logistic regression analysis of pregnancy and birth characteristics and stunting
Variable
OR (95%CI)
p-value
OR* (95%CI*)
p*-value
Father's age
when having
child (years)
22-40
1
1
< 22
1.69 (1.14 – 2.50)
0.009
1.71 (1.15 – 2.50)
0.008
> 40
0.94 (0.73 – 1.21)
0.611
0.94 (0.73 – 1.21)
0.611
Mother's age
when having
child (years)
22-40
1
1
< 22
1.19 (0.79 – 1.78)
0.394
1.24 (0.83 – 1.86)
0.292
> 40
1.55 (0.90 – 2.67)
0.111
1.53 (0.89 – 2.62)
0.127
Mother was
stressed during
pregnancy
No
1
1
Yes
0.83 (0.63 – 1.08)
0.168
0.82 (0.63 – 1.07)
0.143
Mother's weight
increases during
pregnancy (kg)
10 – 15
1
1
< 4
0.81 (0.35 – 1.89)
0.633
0.36 (0.09 – 1.47)
0.154
4 – 10
1.13 (0.82 – 1.57)
0.461
1.12 (0.87 – 1.51)
0.440
15 – 20
1.22 (0.94 – 1.59)
0.133
1.25 (0.96 – 1.63)
0.100
> 20
1.14 (0.68 – 1.89)
0.622
1.17 (0.70 – 1.95)
0.544
Number of
weeks of
pregnancy
36 – 40
1
< 36
1.56 (1.05 – 2.33)
0.027
1.54 (1.03 – 2.30)
0.037
> 40
1.28 (0.82 – 2.01)
0.281
1.27 (0.81 – 1.99)
0.301
Birth weight
(gram)
2800-3800
1
< 2800
1.44 (1.06 – 1.95)
0.020
1.43 (1.05 – 1.94)
0.023
> 3800
0.93 (0.64 – 1.49)
0.981
0.98 (0.64 – 1.49)
0.927
Delivery modes
Vaginal
delivery
1
Cesarean
section
1.28 (1.03 – 1.58)
0.025
1.23 (1.02 – 1.56)
0.034
Forceps
delivery
2.16 (0.99 – 4.68)
0.052
2.29 (1.05 – 4.98)
0.037
OR, p-values were obtained from univariate logistic regression analysis.
OR*, p*-values were obtained from binary logistic regression analysis adjusted for age and sex.
Table 2 reveals no link between the mother's age, stress status, and pregnancy weight gain with
her child's stunting status. However, it highlights significant associations between the father's age,
gestational weeks, birth weight, delivery mode, and child stunting. Children with younger fathers
(< 22 years old), infants born before 36 weeks, birth weight under 2800 g, and deliveries by
cesarean section or forceps were at higher risk of stunting (p-value < 0.05).
3.1.3. Association of childcare characteristics in the first 2 years of life with stunting
Table 3 displays the results of binary logistic regression analyzing early childcare characteristics
linked to stunting among preschoolers in Hanoi.
Table 3 indicates significant associations between early formula milk consumption and the
timing of solid food introduction (weaning) with stunting in preschoolers (p-value < 0.05). Children
who consumed formula milk in their first 6 months had a 1.27 times higher stunting risk compared
to non-consumers. Early or late weaning (before 4 months or after 7 months) also increased stunting
risk by about 1.5 times. However, no associations were found between breastfeeding initiation,
duration, and stunting among Hanoi preschoolers (p-value > 0.05).
TNU Journal of Science and Technology
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Table 3. Association of childcare characteristics in the first 2 years of life with stunting
Variable
OR (95%CI)
p-value
OR* (95%CI)
p*-value
Breastfeeding
Yes
1
1
No
0.97 (0.70 – 1.35)
0.855
0.98 (0.71 – 1.39)
0.908
Drink formula
milk in the
first 6 months
No
1
1
Yes
1.27 (1.01 – 1.60)
0.045
1.27 (1.01 – 1.60)
0.045
When starting
weaning
In the 6th month
1
1
Before the 5th
month
1.55 (1.03 – 2.33)
0.037
1.59 (1.05 – 2.39)
0.028
After the 7th
month
1.41 (1.07 – 1.86)
0.014
1.43 (1.09 – 1.89)
0.011
When stop
breastfeeding
From the 12th to
the 24th month
1
1
Before the 12th
month
0.83 (0.66 – 1.05)
0.122
0.84 (0.66 – 1.06)
0.138
After the 24th
month
1.41 (0.87 – 1.28)
0.165
1.42 (0.88 – 2.30)
0.156
OR, p-values were obtained from univariate logistic regression analysis.
OR*, p*-values were obtained from binary logistic regression analysis adjusted for age and sex.
3.2. Discussion
Parental age impacts children's health, with older parents at higher risk of genetic abnormalities
affecting the child’s development [12], [13]. A study of 18,335 subjects in the United States noted
worse outcomes (height, obesity, diseases) for children born to mothers under 25 or over 35
compared to those aged 25-34 [13]. However, a study of 24-59-month-old children in Indonesia,
found no association between maternal age and stunting in children [6]. Our study found no
association between high paternal and maternal age and stunting, which may be due to the good
knowledge of contraception and family planning among women in Hanoi [14], leading to
childbearing ages that are neither too young nor too old. However, children whose fathers were
under 22 years old had a risk of stunting 1.71 times higher compared to those whose fathers were
aged 22-40 (Table 2), possibly because young fathers might lack the experience and resources to
properly care for their children, leading to malnutrition.
Maternal mental and physical health during pregnancy has been reported to be associated with
fetal and neonatal growth [8]. A study of 140 mother-child pairs in Indonesia found that maternal
depression during pregnancy has a significant relationship with the incidence of stunted toddlers (r
= 0.170) [15]. Maternal stress during pregnancy increased levels of the hormone cortisol, which
was negatively associated with length-for-age at birth (r = -0.247) but positively associated at 13-
14 months (r = 0.378) [16]. Weight gain during pregnancy is an indicator of maternal nutrient
supply, which in turn affects fetal nutrition. Too much or too little maternal weight gain can
negatively affect fetal development but does not significantly affect the child's later height [17].
This suggest that infant catch-up growth with lower birth weights continues beyond early infancy
[16] explaining the lack of association between maternal stress, maternal weight gain during
pregnancy and stunting in our study.
Proper nourishment is crucial for fetal development and bone strength from conception to the
end of pregnancy. Between the 36th and 40th weeks, the fetal body is nearly fully formed [18],
explaining our finding that preterm birth before 36 weeks increases the risk of stunting by 1.54
times. Children with a birth weight under 2.8 kg have an increased risk of stunting (OR = 1.43),
similar to findings in Indonesia and Bangladesh [7], [19]. Low birth weight infants are more
susceptible to infections, jaundice, anemia, chronic lung conditions, fatigue, and decreased appetite
compared to normal birth weight infants [7].