Maternal serum retinol and β-carotene concentrations and neonatal bone mineralization: results from the Southampton Women's Survey cohort

BACKGROUND: Studies in older adults and animals have suggested contrasting relations between bone health and different vitamin A compounds. To our knowledge, the associations between maternal vitamin A status and offspring bone development have not previously been elucidated.

OBJECTIVE: We examined the associations between maternal serum retinol and β-carotene concentrations during late pregnancy and offspring bone mineralization assessed at birth with the use of dual-energy X-ray absorptiometry.

DESIGN: In the Southampton Women's Survey mother-offspring birth cohort, maternal health, lifestyle, and diet were assessed prepregnancy and at 11 and 34 wk of gestation. In late pregnancy, maternal serum retinol and β-carotene concentrations were measured. Offspring total body bone mineral density (BMD), bone mineral content (BMC), and bone area (BA) were measured within 2 wk after birth.

RESULTS: In total, 520 and 446 mother-offspring pairs had measurements of maternal serum retinol and β-carotene, respectively. Higher maternal serum retinol in late pregnancy was associated with lower offspring total body BMC (β = -0.10 SD/SD; 95% CI: -0.19, -0.02; P = 0.020) and BA (β = -0.12 SD/SD; 95% CI: -0.20, -0.03; P = 0.009) but not BMD. Conversely, higher maternal serum β-carotene concentrations in late pregnancy were associated with greater total body BMC (β = 0.12 SD/SD; 95% CI: 0.02, 0.21; P = 0.016) and BA (β = 0.12 SD/SD; 95% CI: 0.03, 0.22; P = 0.010) but not BMD.

CONCLUSIONS: Maternal serum retinol and β-carotene concentrations had differing associations with offspring bone size and growth at birth: retinol was negatively associated with these measurements, whereas β-carotene was positively associated. These findings highlight the need for further investigation of the effects of maternal retinol and carotenoid status on offspring bone development.