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European Journal of Applied Sciences – Vol. 10, No. 2
Publication Date: April 25, 2022
DOI:10.14738/aivp.102.11735. Raje, S., & Rao, S. (2022). Maternal Diet Influences Association of Gestational Weight Gain and Birth Weight Among Undernourished
Mothers. European Journal of Applied Sciences, 10(2). 15-26.
Services for Science and Education – United Kingdom
Maternal Diet Influences Association of Gestational Weight Gain
and Birth Weight Among Undernourished Mothers
Swati Raje
Department of Community Medicine
MIMER Medical College, Talegaon Dabhade, Maharashtra, India
Shobha Rao
Society for Initiatives in Nutrition and Development, Pune 411 007, India
ABSTRACT
Objective: Maternal nutrition intervention improves birth outcomes in
undernourished but not in well-nourished populations. Therefore, objective was to
examine its role in association of weight gain and pregnancy outcome in
undernourished mothers. Design: Prospective study Setting: Obstetrics and
Gynaecology out patients department of Rural Hospital Talegaon, Participants:
Mothers (n=370) registering within 20 weeks of gestation were studied for
socioeconomic variables, diet, anthropometric measurements and were followed
up till delivery. Results: Mothers were undernourished with mean weight 45.9±7.3
kg, height150.8±6.1 cm and BMI 20.2±3.1kg/m2. In fact proportion of mothers
below LBW risk cur off for weight (38Kg), height (<145 cm) and BMI(18.5 kg/m2 )
was respectively 9.8 %, 8.6 % and 32.8%. Mothers in lower tertile of weight (<42.5
Kg), BMI (<18.5Kg/m2) body fat (<21.8%) had babies with significantly lower birth
weights with highest prevalence of LBW. Maternal BMI associated inversely with
weight gain but positively with birth weight indicating that foetal growth was not
benefitted fully by gained weight in undernourished mothers. Consumption of
milk/milk products, fruits, non-vegetarian foods, dal and roti was associated with
birth weight but not with weight gain. Comparison of mothers of LBW and normal
weight babies within low (18.5 kg/m2) and high (≥21.1kg/m2) BMI groups showed
that consumption of milk was discriminatory, indicating importance of proteins
and micronutrients in facilitating foetal growth. Conclusion: Consumption of milk
facilitated sparing of gained weight for foetal growth among undernourished
mothers and promoting it could be a simple public health approach for prevention
of LBW in rural India.
Key words: Maternal diet, weight gain, birth weight, undernourished mothers
INTRODUCTION
Almost 20 million low birth weight infants are born each year, a large majority of those births
occurring in low and middle income countries (LMIC). Poor foetal growth in developing world
is largely attributed to widespread maternal undernutrition. High prevalence of LBW in
developing countries is therefore reflection of a more severe and massive problem related to
maternal undernutrition. In fact, poor nutritional status at conception, low gestational weight
gain due to inadequate dietary intake and short maternal stature due to mothers own
childhood under nutrition and / or infection are believed to be the major determinants for LBW
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European Journal of Applied Sciences (EJAS) Vol. 10, Issue 2, April-2022
Services for Science and Education – United Kingdom
in developing countries (1). It is worthwhile to note that the countries where high proportions
of LBW are seen are also the countries where women have low body mass index indicating
maternal undernutrition.
Although poor maternal nutritional status is a major determinant of LBW, the factors
responsible range from socio demographic to genetic, illustrating a wide spectrum of
underlying causes. For example, poor socio economic environment is known to affect food
availability (2 ), the work load of the mother (3) and important decisions like seeking antenatal
care during pregnancy (4) that influence birth outcome. Equally important are the
demographic factors like early age at marriage and conception (5), delayed age of menarche
coupled with early conception (6), short spacing (<2 yr) between successive deliveries (7, 8, 9,
10) and the history of repeated abortions make women from low socio-economic class more
vulnerable for poor pregnancy outcome (11).
Mother’s nutritional status prior to conception and her nutrition through pregnancy influence
birth weight considerably. It is believed that the impact of poor nutritional status of mother is
more pervasive than the impact of other factors on birth weight. In particular, maternal pre
pregnancy weight, an indicator of current nutritional status, is known to have independent
influence on birth weight. (12,13,14). Similarly, statistically significant associations between
short maternal stature, an indicator of past undernutrition, and adverse birth outcome are
reported (15) using extensive meta-analysis of large data sets from LMIC.
Gestational weight gain is yet another important factor associated with pregnancy outcome but
most of the evidence is from developed countries (16). Therefore, these associations may differ
by countries, ethnic diversity and especially among undernourished populations (17). For, in
less developed Asian countries women achieve less gestational weight gain than IOM
recommendations. Secondly, less is known about weight gain by time in pregnancy and its
influence on birth size. Finally, inadequacy of key nutrients required for foetal growth may
affect weight gain and its association with pregnancy outcome.
Although importance of maternal nutrition to foetal development and birth outcomes has been
clearly demonstrated in experimental animal studies, the findings of studies in humans are
much less consistent (18 ). Unfortunately, maternal diets in most developing countries are often
inadequate both in macronutrients and micronutrients. But, studies of energy protein
supplementation during pregnancy have produced varying and sometimes conflicting results
(19). Similarly, available data on relationship of maternal micronutrient status with actual
pregnancy outcome is extremely scanty and the more logical approach of multiple
micronutrient supplements has been inadequately tested (20). Further, nutritional insults
during different periods of gestation have differing effects on birth. For example, acute severe
maternal malnutrition may adversely affect the birth weight of the foetus especially when the
exposure is during the third trimester of pregnancy (21) while early work (22) has shown that
undernutrition in early intra uterine life tends to produce small but normally proportional
animals whereas undernutrition later in development leads to selective organ damage and
disproportionate growth. Maternal nutrition is thus of paramount importance and needs
critical understanding for planning effective strategies to improve birth outcome.
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Raje, S., & Rao, S. (2022). Maternal Diet Influences Association of Gestational Weight Gain and Birth Weight Among Undernourished Mothers.
European Journal of Applied Sciences, 10(2). 15-26.
URL: http://dx.doi.org/10.14738/aivp.102.11735
In a recent study (23) improved maternal intakes of milk in early gestation and of GLV and fruit
in late gestation were reported to result in improved fetal growth and authors suggest that
these foods probably provide a more effective combination of nutrients than do conventional
supplements that contain only one or two micronutrients or macronutrients. Milk intake in
pregnancy was also observed (24) to be associated with higher birth weight for gestational age,
lower risk of SGA, and higher risk of LGA while a study in Ghana (25) reports that increase in
dietary diversity is effective in reduction of prevalence of LBW. The implication is that, specific
foods providing specific nutrients may be of importance rather than absolute intake of calories
or proteins. The present study thus attempts to investigate the associations between maternal
nutritional status at registration, nutrition and weight gain during gestation with birth weight.
MATERIALS AND METHODS
Present study was a hospital based prospective study, carried out at Dr. Bhausaheb Sardesai
Rural Hospital Talegaon, attached to MIMER medical college.
Subjects - The study population comprised of Antenatal Care cases who registered at the
Obstetrics and Gynaecology out patients department of the hospital within 20 weeks of
gestation. Considering 35% prevalence of LBW with 5% tolerance estimated sample size was
425 cases allowing for 15% loss to follow up. Clinically apparently normal ANC cases within 18
to 40 years of age, were enrolled in the study after obtaining their oral informed consent. Out
of 459 initially enrolled, there were exclusions due to abortions (21), still births (3 ), intra
uterine growth retarded (IUGR) (2). Of the remaining 433 cases, exclusions due to multiple
pregnancies (4), major illness (thyroid -1 and pregnancy induced hypertension-1), changing
the place of delivery (6) and premature deliveries (51), data on 370 full term mothers is
analysed. Ethical clearance was sought from Ethical Committee of MIMER medical college.
Qualitative information: Maternal socio economic and demographic information was
collected on each enrolled woman at the time of registration using a structured and validated
questionnaire. It comprised of size of the family, monthly income, education and occupation of
the mother as well as her husband. The demographic information about her age at menarche,
marriage and at registration was also recorded. Similarly, obstetric information on variables
like parity, spacing and previous abortions, if any, was recorded for each mother. Maternal
activity was also recorded as time spent in domestic work, leisure activities and work done
outside, using pretested activity questionnaire.
Anthropometric measurements - Maternal height was measured (up to 0.1 cm) using
stadiometer(Standard Steel Co. Model SECA213, India), weight was measured using (up to 100
g) digital weighing balance (Smart Care Co. Model SCS110A, India) , Body fat (%) was recorded
using body fat analyser (HBF300, OMRON Corporation, Japan) at each ANC visit. Babies were
measured at birth using digital weighing scale (Homedics Group Ltd. Model Salter 914, India)
was used for measuring length.
Maternal dietary intake – Dietary intake was assessed using pre tested food frequency
questionnaire (FFQ) to record consumption of various foods and their frequency in last one
month. It covered total of 54 food items divided into 13 groups such as milk, milk products,
cereals, lentils, legumes, vegetables, green leafy vegetables, fruits, non-vegetarian foods, snacks,
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European Journal of Applied Sciences (EJAS) Vol. 10, Issue 2, April-2022
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bakery products etc. Amount of food intake was measured in terms of number of roties and in
terms of serving spoons of standard size for other foods. Frequency of consumption in terms of
once, twice or more in a day / week or month was noted.
Statistical methods – Variables deviating from normality were transformed for achieving it y
before using them in the statistical analysis. Means of two groups were compared using‘t’ test
while linearity in group means was tested using ANOVA. Logistic regression was done to
estimate odd ratio (OR) for risk of LBW in higher category considering lower category as
reference category for various risk factors. FFQ scores were used as grouped variable.
Statistical analysis of data thus collected was done using SPSS 19.0 version.
RESULTS
Socio economic, demographic background of mothers
Most mothers (56.5%) had family size < 5 and over 80% of mothers and their husbands had
education only up to 10th std (Table 1). Mothers were either housewives or were engaged in
farming (92%). Their husbands were also largely (47.1 %) engaged in unskilled jobs and
almost all had low monthly income. Mean age at registration was 22.6 ± 3.3 yr and majority
(73.5%) of mothers were young i.e. below <25 yr.
Maternal nutritional status and birth weight
Mothers were overtly undernourished (Table 1). They were thin (mean weight 45.9±7.3 kg)
and short (mean height 150.9±5.9 cm). Almost 9.6 % had lower weight than risk cut off (38 kg)
and 8.4 % were shorter than risk cur off (145 cm) for height, which are considered to be risk
cut offs for LBW. They were undernourished (mean BMI 20.2±3.1 kg/m2) and almost 32.8 %
mothers had BMI below 18.5 kg/m2 indicating chronic energy deficiency. Their mean body fat
was (24.7± 6.4 %) and indicated lower body energy source. Consequently, the overall mean
birth weight was only 2571±311 g and the prevalence of LBW was 41.4 %.
Maternal nutritional status is known to be a major determinant of birth weight and all the three
anthropometric indicators of mother’s nutritional status viz., weight, BMI, and body fat; showed
positive association with birth weight (Table 2). Thus, mean birth weight of the babies born to
mothers in the lowest tertile of weight (2541±319g), or BMI (2521±309g), or body fat (2526 ±
306g) was lowest and increased significantly (p<0.05) from lowest to highest tertile for each
of the indicator. Thus mothers with poor weight (<42.5 Kg ), lower BMI (<18.5 Kg/m2 ) and
lower body fat (<21.8%) had babies with significantly lower birth weights compared to their
counterparts. Consequently, the prevalence of LBW in the lowest tertile was highest but did not
decrease significantly. In fact, even in the highest tertiles of these indicators it remained quite
high, almost above 35%.
Maternal nutritional status and weight gain
Gestational weight gain is one of the major determinants of birth weight. The overall mean
gestational weight gain was 7.38 ± 2.6 Kg (give mean gain for lbw and normal) and though it
was correlated (r=0.129; p=0.016) with birth weight, the explained variation in birth weight
was even <5%. Weight gain of mothers of LBW babies was comparable in early pregnancy but
fell between 20th to 25th weeks and remained low thereafter. They seemed to gain with faster
rate only towards the end of gestation (Fig1). Mean weight gain by tertiles of maternal
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European Journal of Applied Sciences (EJAS) Vol. 10, Issue 2, April-2022
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critical importance and needs understanding of role of macro and micronutrients in fetal
growth. We observed that food consumption was not associated with weight gain but was
correlated with birth weight. Moreover, among undernourished mothers consumption of dal
(pulses, the source of protein) and milk products (micronutrients like calcium, B12) made the
difference in mothers of LBW and normal weight babies indicating possible role in the
process/mechanism of sparing the gained weight for foetal growth.
Pre-pregnancy BMI and gestational weight gain is indicator of maternal reserves for foetal
growth. Mothers in our study were thin, short and 32.8% were below the BMI of 18.5 indicating
chronic energy deficiency. Mean maternal weight was comparable with those reported in
various rural areas from for Maharashtra (23); for Karnataka (28) and for Uttar Pradesh (29).
All the maternal nutritional status indicators viz., maternal weight, BMI and body fat; showed
significant positive association with birth weight and inverse association with prevalence of
LBW. In particular, mothers in lower tertile of weight (<42.5 Kg) or BMI (<18.5) had lowest
birth weight and highest prevalence of LBW.
Weight gain on the other hand was inversely associated with maternal nutritional status. Thus
mothers with poor maternal pre-pregnancy BMI (or weight /body fat) gained significantly
more compared to mothers with higher BMI (or weight /body fat). Similar observations are
reported among Indonesian women (16). Most women achieved less gestational weight gain
than IOM recommendation. Though total weight gain for mothers of LBW was comparable with
mothers of normal weight babies, they appeared to gain less in second trimester (beyond 20
wks.) compared to their counterpart indicating influence of weight change by time in pregnancy
on outcome. It has been reported that weight gain in early pregnancy and not in third trimester
predicted birth size (30,31).
Nutritional deficiencies are common in women of reproductive age in developing countries and
epidemiological and biological studies suggest that specific nutritional deficiencies can
influence the pregnancy outcome. For example, in a comparative study on women who
delivered LBW babies with those who delivered normal weight babies, it was observed that the
maternal diets in the former group were deficient in folate, iron and calcium (32). Placental
and fetal growth is believed to be most vulnerable to maternal nutrition status, especially
protein and micronutrients, in the early pregnancy (first trimester), a period of peri- implantation and of rapid placental development (33). Although nutrient requirement in the
first trimester are quantitatively small, nutritional deprivations during this period can
adversely affect placental structure and indirectly ultimately the birth weight. In our study
nutritional assessment at registration showed that higher consumption of milk and milk
products, fruits, non-vegetarian foods, dal and roti was associated with higher birth weight but
not with higher weight gain.
Finally, role of nutrition was further revealed when we compared consumption of mothers of
LBW and normal weight babies by considering their BMI (whether low or high) at registration.
When maternal BMI at registration was high (>21Kg/m2) consumption of non-vegetarian foods
made a difference in birth weight. In contrast, when mothers were undernourished (<18.5
Kg/m2) at registration, in addition to non-vegetarian foods consumption of milk and milk
products and dal made the difference. Review of studies published in the recent decade also
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Raje, S., & Rao, S. (2022). Maternal Diet Influences Association of Gestational Weight Gain and Birth Weight Among Undernourished Mothers.
European Journal of Applied Sciences, 10(2). 15-26.
URL: http://dx.doi.org/10.14738/aivp.102.11735
reports a significant positive association between maternal milk consumption and fetal growth
as well as infant birth weight and suggests its importance as a source of protein and other
valuable nutrients (34, 35). In particular, milk is a rich and major source of calcium and B12 in
vegetarian diets. Our data therefore suggest that among undernourished mothers despite
higher weight gain, its sparing for foetal growth is perhaps conditioned by maternal intake of
calcium as it has been reported in several animal studies that calcium triggers lipolysis. Further,
it renders support to the observation (36) that this action of calcium is profoundly seen at levels
of energy restriction. We have reported earlier that almost 75% of the mothers were having
calorie intake below 80% of RDA while 50% were below this cut off for protein intake (37).
CONCLUSION
In conclusion, the relationships of pre pregnancy BMI, weight gain and pregnancy outcome may
differ in undernourished populations. The observation that maternal underweight (or low BMI)
was associated with significant risk of LBW was also reported by recent studies (38, 39)
attempting meta-analysis. Improvement of nutrition and health status of adolescent girls is of
vital importance since it is inextricably linked with the quality of the next generation as
reported from study that followed birth cohort through their pregnancy (40). Secondly, besides
the known influence of early pregnancy (<20 wks), our observation indicated that the birth
weight appeared to be refractory to effects of weight change beyond 20th week. Since weight
gain in third trimester (>=25 wk) does not show association with birth weight (30) the
suggestion is that first 20 weeks could be the critical window for nutrition interventions during
gestation in undernourished mothers.
Finally, in the event of scarce data on maternal nutritional intakes in undernourished mothers,
our observation that consumption of dal and milk was discriminatory in mothers of LBW and
normal weight babies has important implications. Because, in the event of low BMI before
conception, dietary modification offers the only hope for improving birth weight. Food based
interventions, using milk or distributing extra dal through PDS (Public Distribution Scheme) to
pregnant mothers would be helpful as these foods are part of the conventional food basket.
Alternatively administrating health education aimed to create nutritional awareness and
motivate rural mothers for promoting consumption of milk/ milk products and dal daily during
gestation will be simple public health approach for tackling the massive problem of low birth
weight in rural India.
ACKNOWLEDGEMENTS
We acknowledge the support of the management of MIMER medical college and department of
Community medicine, MIMER Medical College for giving full support to do this study.
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Raje, S., & Rao, S. (2022). Maternal Diet Influences Association of Gestational Weight Gain and Birth Weight Among Undernourished Mothers.
European Journal of Applied Sciences, 10(2). 15-26.
URL: http://dx.doi.org/10.14738/aivp.102.11735
Table 4: Mean birth weight by consumption of different foods.
Food item Frequency of consumption Mean birth
weight (g)
P +
Milk products Yes
No
2605 ± 310
2540 ± 309
.05
Milk & milk product
consumption
Yes
No
2601 ± 303
2524 ± 318
.02
Fruit < once/month
Once/mo to once /d
≥ once/d
2554 ± 300
2511 ± 321
2633 ± 317
.05
Non vegetarian food < Once /wk
≥ once /wk
2532 ± 311
2604 ± 307
.03
Roti <2/d
2-4/d
≥4/d
2534±291
2546±318
2657±309
.01
Dal (Pulses) < 1/wk
1/wk to alternate day
≥ alternate day
2534 ± 321
2496 ± 289
2607 ± 310
0.03
+ p for difference / trend in group means
Table 5: Comparison of mothers of LBW and normal babies in low and high BMI tertiles
Undernourished
(BMI<18.5) Maternal characteristics
Well nourished
(BMI >=21.1)
Normal
(n=56)
LBW (n=57) Normal
(n=69)
LBW (n=40)
40.9 ± 3.0 39.3 ± 3.7* Maternal weight (Kg) 53.2 ± 7.2 53.7 ± 7.1
17.4 ± 0.75 17.0±1.2* BMI (Kg / m2) 23.5 ± 2.5 23.9 ± 2.6
20.3 ± 4.3 19.4 ± 4.7 Body fat (%) 29.7 ± 5.0 31.0 ± 5.7
7.83 ± 2.3 7.99 ± 1.7 Gestational weight gain (Kg) 6.77 ± 2.1 6.77 ± 2.1
2709 ± 285 2314 ± 175** Mean Birth weight (g) 2757 ± 293 2386 ± 97**
53.6 35.7*
Milk products
≥ once/wk 58.0 47.5
66.1 50.0*
Total milk
≥ once/wk 68.1 64.3
37.5 16.1*
Legumes
< once/wk 26.1 35.7
65.5 43.6*
Non veg. foods
≥ once/wk 62.3 43.9*