Impact of Maternal Vitamin D Levels on Offspring Bone Development: Systematic Review.

BACKGROUND

Maternal vitamin D is essential for fetal calcium homeostasis and skeletal development. The long-term impact of maternal vitamin D status during pregnancy on offspring bone health remains unclear, especially in populations with high sun exposure yet persistent deficiency. This systematic review synthesizes cohort study on the association between maternal serum 25-hydroxy-vitamin D (25[OH]D) levels during pregnancy and bone outcomes in offspring.

METHODS

A total of 19 cohort studies, comprising 12,835 mother-offspring pairs across diverse geographic regions, were systematically reviewed. Offspring bone health indicators included bone mineral content (BMC), bone mineral density (BMD), bone turnover biomarkers, and fracture risk, assessed using dual energy X-ray absorptiometry (DXA), quantitative ultrasound (QUS), and biochemical markers. Heterogeneity in vitamin D thresholds, measurement timing, and follow-up duration was noted.

RESULTS

The findings were heterogeneous and often sex-specific. Some studies reported a positive association between higher maternal 25(OH)D levels and increased BMC/BMD, particularly in male offspring. Others showed no significant association after adjusting for maternal and neonatal confounders. Biomarker analyses generally supported an inverse relationship between maternal vitamin D deficiency and fetal bone turnover markers. However, evidence remains inconclusive regarding the benefits of prenatal vitamin D supplementation on long-term skeletal outcomes.

CONCLUSIONS

Maternal vitamin D status appears to influence offspring bone development in a complex and multifactorial manner. Effects may be modified by child sex, timing of deficiency during gestation, and genetic factors. Future studies should prioritize standardized measurement protocols and expand cohort representation in under-researched regions, notably Southeast Asia, to inform public health guidelines and targeted interventions.