Circulating 25-Hydroxyvitamin D₃ in Pregnancy and Infant Neuropsychological Development

OBJECTIVE: To investigate whether circulating 25-hydroxyvitamin D₃ [25(OH)D₃] concentration in pregnancy is associated with neuropsychological development in infants.

METHODS: The Spanish population-based cohort study INfancia y Medio Ambiente Project recruited pregnant women during the first trimester of pregnancy between November 2003 and February 2008. Completed data on 1820 mother-infant pairs were used. Maternal plasma 25(OH)D₃ concentration was measured by high-performance liquid chromatography in pregnancy (mean 13.5±2.1 weeks of gestation). Offspring mental and psychomotor scores were assessed by trained psychologists at age 14 months (range, 11–23) by using the Bayley Scales of Infant Development. β-Coefficients with 95% confidence intervals (CIs) of mental and psychomotor scores associated with continuous or categorical concentrations of maternal plasma 25(OH)D₃ were calculated by using linear regression analysis.

RESULTS: The median plasma value of 25(OH)D₃ in pregnancy was 29.6 ng/mL (interquartile range, 21.8–37.3). A positive linear relationship was found between circulating concentrations of maternal 25(OH)D₃ concentrations in pregnancy and mental and psychomotor scores in the offspring. After adjustment for potential confounders, infants of mothers with 25(OH)D₃ concentrations in pregnancy >30 ng/mL showed higher mental score (β = 2.60; 95% CI 0.63–4.56) and higher psychomotor score (β = 2.32; 95% CI 0.36–4.28) in comparison with those of mothers with 25(OH)D₃ concentrations <20 ng/mL.

CONCLUSIONS: Higher circulating concentration of maternal 25(OH)D₃ in pregnancy was associated with improved mental and psychomotor development in infants.