In The Pune Maternal Nutrition Study, vitamin B12 deficiency was seen in 65% of pregnant women, folate deficiency was rare. Maternal total homocysteine concentrations were inversely associated with offspring birthweight, and low vitamin B12 and high folate concentrations predicted higher offspring adiposity and insulin resistance. These findings guided a nested pre-conceptional randomised controlled trial ‘Pune Rural Intervention in Young Adolescents’. The interventions included: (1) vitamin B12+multi-micronutrients as per the United Nations International Multiple Micronutrient Antenatal Preparation, and proteins (B12+MMN), (2) vitamin B12 (B12 alone), and (3) placebo. Intervention improved maternal pre-conceptional and in-pregnancy micronutrient nutrition. Gene expression analysis in cord blood mononuclear cells in 88 pregnancies revealed 75 differentially expressed genes between the B12+MMN and placebo groups. The enriched biological processes included G2/M phase transition, chromosome segregation, and nuclear division. Enriched pathways included, mitotic spindle checkpoint and DNA damage response while enriched human phenotypes were sloping forehead and decreased head circumference. Fructose-bisphosphatase 2 (FBP2) and Cell Division Cycle Associated 2 (CDCA2) genes were under-expressed in the B12 alone group. The latter, involved in chromosome segregation was under-expressed in both intervention groups. Based on the role of B-complex vitamins in the synthesis of nucleotides and S-adenosyl methionine, and the roles of vitamins A and D on gene expression, we propose that the multi-micronutrient intervention epigenetically affected cell cycle dynamics. Neonates in the B12+MMN group had the highest ponderal index. Follow-up studies will reveal if the intervention and the altered biological processes influence offspring diabesity.

Maternal size, weight gain in pregnancy, fetal gender, environment and gestational age are known determinants of birth weight. It is not clear which component of maternal weight or gained weight during pregnancy influences birth weight. We evaluated the association of maternal total body water measured by the deuterium dilution technique (TBW-D2O) at 17 and 34 weeks of gestation with birth weight. A secondary aim was to examine the utility of bioimpedance spectroscopy (BIS) to determine total body water (TBW-BIS) in pregnancy. At 17 and 34 weeks of pregnancy, ninety-nine women (fifty-one rural and forty-eight urban) from Pune, India had measurements of body weight, TBW-D2O, TBW-BIS and offspring birth weight. At 17 weeks of gestation, average weights for rural and urban women were 45⋅5 ± 4⋅8 (sd) and 50⋅7 ± 7⋅8 kg (P < 0⋅0001), respectively. Maternal weight gains over the subsequent 17 weeks for rural and urban women were 6⋅0 ± 2⋅2 and 7⋅5 ± 2⋅8 kg (P = 0⋅003) and water gains were 4⋅0 ± 2⋅4 and 4⋅8 ± 2⋅8 kg (P = 0⋅092), respectively. In both rural and urban women, birth weight was positively, and independently, associated with gestation and parity. Only for rural women, between 17 and 34 weeks, was an increase in dry mass (weight minus TBW-D2O) or a decrease in TBW-D2O as a percentage of total weight associated with a higher birth weight. At both 17 and 34 weeks, TBW-BIS increasingly underestimated TBW-D2O as the water space increased. Differences in body composition during pregnancy between rural and urban environments and possible impacts of nutrition transition on maternal body composition and fetal growth were demonstrated.

Neurocognitive development is a dynamic process over the life course and is influenced by intrauterine factors as well as later life environment. Using data from the Pune Maternal Nutrition Study from 1994 to 2008, we investigate the association of in utero, birth, and childhood conditions with offspring neurocognitive development in 686 participants of the cohort, at age 12 years. The life course exposure variables in the analysis include maternal pre-pregnancy size and nutrition during pregnancy, offspring birth measurements, nutrition and physical growth at age 12 years along with parental education and socio-economic status. We used the novel Bayesian Model Averaging (BMA) approach; which has been shown to have better predictive performance over traditional tests of associations. Our study employs eight standard neurocognitive tests that measure intelligence, working memory, visuo-conceptual and verbal learning, and decision-making/attention at 12 years of age. We control for nutritional-metabolic information based on blood measurements from the pregnant mothers and the children at 12 years of age. Our findings highlight the critical role of parental education and socio-economic background in determining child neurocognitive performance. Maternal characteristics (pre-pregnancy BMI, fasting insulin during pregnancy) and child height at 12 years were also robust predictors on the BMA. A range of early factors – such as maternal folate and ferritin concentrations during pregnancy, and child’s head circumference at birth – remained important determinants of some dimensions of child’s neurocognitive development, but their associations were not robust once we account for model uncertainty. Our results suggest that intrauterine influences on long- term neurocognitive outcomes may be potentially reversible by post-birth remediation. In addition to the current nutritional interventions, public health policy should also consider social interventions in children born into families with low socio-economic status to improve human capital.

With type 2 diabetes presenting at younger ages, there is a growing need to identify biomarkers of future glucose intolerance. A high (20%) prevalence of glucose intolerance at 18 years was seen in women from the Pune Maternal Nutrition Study (PMNS) birth cohort. We investigated the potential of circulating microRNAs in risk stratification for future pre-diabetes in these women. Here, we provide preliminary longitudinal analyses of circulating microRNAs in normal glucose tolerant (NGT@18y, N = 10) and glucose intolerant (N = 8) women (ADA criteria) at 6, 12 and 17 years of their age using discovery analysis (OpenArray™ platform). Machine-learning workflows involving Lasso with bootstrapping/leave-one-out cross-validation identified microRNAs associated with glucose intolerance at 18 years of age. Several microRNAs, including miR-212-3p, miR-30e-3p and miR-638, stratified glucose-intolerant women from NGT at childhood. Our results suggest that circulating microRNAs, longitudinally assessed over 17 years of life, are dynamic biomarkers associated with and predictive of pre-diabetes at 18 years of age. Validation of these findings in males and remaining participants from the PMNS birth cohort will provide a unique opportunity to study novel epigenetic mechanisms in the life-course progression of glucose intolerance and enhance current clinical risk prediction of pre-diabetes and progression to type 2 diabetes.

The ‘thrifty phenotype’ hypothesis proposed that fetal undernutrition increases risk of diabetes in later life. Undernourished low birthweight Indian babies are paradoxically more adipose compared to well-nourished European babies, and are at higher risk of diabetes in later life. Twin pregnancies are an example of in utero growth restrictive environment due to shared maternal nutrition. There are few studies of body composition in twins. We performed secondary analysis of anthropometric body composition of twins and singletons in Guinea-Bissau, an economically deprived African country.

Anthropometric data were available on 7–34 year-old twins (n = 209, 97 males) and singletons (n = 182, 86 males) in the Guinea-Bissau Twin Registry at the Bandim Health Project. Twins had lower birthweight (2420 vs 3100 g, p < 0.001); and at follow-up, lower height (HAZ mean Z-score difference, −0.21, p = 0.055), weight (WAZ −0.73, p = 0.024) and BMI (BAZ −0.22, p = 0.079) compared to singletons but higher adiposity (skinfolds: +0.33 SD, p = 0.001). Twins also had higher fasting (+0.38 SD, p < 0.001) and 2-hour OGTT glucose concentrations (+0.29 SD, p < 0.05). Linear mixed-effect model accounting for intrapair correlations and interactions confirmed that twins were thinner but fatter across the age range. Data on maternal morbidity and prematurity were not available in this cohort.

African populations are known to have a muscular (less adipose) body composition. Demonstration of a thin-fat phenotype in twins in a low socio-economic African country supports the thesis that it could be a manifestation of early life undernutrition and not exclusive to Indians. This phenotype could increase risk of diabetes and related conditions.

Our objective was to investigate associations of body size (birth weight and body mass index (BMI)) and growth in height, body fat (adiposity) and lean mass during childhood and adolescence, with risk markers for diabetes in young South Asian adults. We studied 357 men and women aged 21 years from the Pune Children’s Study birth cohort. Exposures were 1) birth weight, 21-year BMI, both of these mutually adjusted, and their interaction, and 2) uncorrelated conditional measures of growth in height and proxies for gain in adiposity and lean mass from birth to 8 years (childhood) and 8 to 21 years (adolescence) constructed from birth weight, and weight, height, and skinfolds at 8 and 21 years. Outcomes were plasma glucose and insulin concentrations during an oral glucose tolerance test and derived indices of insulin resistance and secretion. Higher 21-year BMI was associated with higher glucose and insulin concentrations and insulin resistance, and lower disposition index. After adjusting for 21-year BMI, higher birth weight was associated with lower 120-min glucose and insulin resistance, and higher disposition index. In the growth analysis, greater adiposity gain during childhood and adolescence was associated with higher glucose, insulin and insulin resistance, and lower disposition index, with stronger effects from adolescent gain. Greater childhood lean gain and adolescent height gain were associated with lower 120-min glucose and insulin. Consistent with other studies, lower birth weight and higher childhood weight gain increases diabetes risk. Disaggregation of weight gain showed that greater child/adolescent adiposity gain and lower lean and height gain may increase risk.