Associations of maternal and fetal vitamin D status with childhood body composition and cardiovascular risk factors.

Maternal vitamin D deficiency during pregnancy may have persistent adverse effects on childhood growth and development. We examined whether 25-hydroxyvitamin D (25(OH)D) concentrations during pregnancy and at cord blood were associated with childhood body composition and cardiovascular outcomes. This study was embedded in a population-based prospective cohort in Rotterdam, The Netherlands, among 4,903 mothers and their offspring. We measured 25(OH)D concentrations at a median gestational age of 20.4 weeks (95% range 18.5-23.4 weeks) and at birth (40.1 weeks [95% range 35.8-42.3 weeks]). 25(OH)D concentrations were categorized into severely deficient (<25.0 nmol/L); deficient (25.0 to 49.9 nmol/L); sufficient (50.0 to 74.9 nmol/L) and optimal (≥75.0 nmol/L). At 6 years, we measured childhood body mass index; fat and lean mass by Dual-energy X-ray Absorptiometry; blood pressure; and serum cholesterol, triglycerides, and insulin concentrations. Compared with children from mothers with optimal 25(OH)D concentrations (≥75.0 nmol/L), those of severely deficient vitamin D (<25.0 nmol/L) mothers had a 0.12 standard deviation score (SDS); (95% Confidence Interval (CI) [0.03, 0.21]) higher fat mass percentage and a 0.13 SDS (95% CI [-0.22, -0.04]) lower lean mass percentage. These associations remained after adjustment for current child vitamin D status. Maternal and cord blood 25(OH)D concentrations were not associated with cardiovascular risk factors in childhood. In conclusion, severe maternal 25(OH)D deficiency (<25.0 nmol/L) during pregnancy is associated with an adverse childhood body composition profile, but we did not observe evidence for an association with childhood cardiovascular risk factors. Further studies are needed to replicate our findings, to examine the underlying mechanisms, the causality of the associations, and the potential for public health interventions.