Context/Objective: Bone mass is influenced by genetic and environmental factors. Recent studies have highlighted associations between maternal nutritional status during pregnancy and bone mass in the offspring. We hypothesized that maternal calcium intakes and circulating micronutrients during pregnancy are related to bone mass in Indian children.

Design/Setting/Participants/Main outcome measures: Nutritional status was measured at 18 and 28 weeks gestation in 797 pregnant rural Indian women. Measurements included anthropometry, dietary intakes (24-hour recall and food frequency questionnaire), physical workload (questionnaire) and circulating micronutrients (red cell folate and plasma ferritin, vitamin B12 and vitamin C). Six years post-natally, total body and total spine bone mineral content (BMC) and bone mineral density (BMD) were measured using Dual energy x-ray Absorptiometry (DXA) in the children (n = 698 out of 762 live births) and both parents.

Results: Both parents' DXA measurements were positively correlated with the equivalent measurements in the children (P < 0.001 for all). The strength of these correlations was similar for fathers and mothers. Children of mothers who had a higher frequency of intake of calcium-rich foods during pregnancy (milk, milk products, pulses, non-vegetarian foods, green leafy vegetables, fruit) had higher total and spine BMC and BMD, and children of mothers with higher folate status at 28 weeks gestation had higher total and spine BMD, independent of parental size and DXA measurements.

Conclusions: Modifiable maternal nutritional factors may influence bone health in the offspring. Fathers play a role in determining their child's bone mass, possibly through genetic mechanisms or through shared environment.