Preconception and prenatal vitamin D associations with positive behavioral health in Black children.

Background: Low levels of vitamin D during pregnancy are associated with offspring behavioral problems but little is known about pre-pregnancy influences. Additionally, Black American individuals are underrepresented in studies, limiting translational impact. We tested independent and interactive effects of preconception and prenatal vitamin D in Black women in relation to positive behavioral and emotional outcomes in early childhood.

Methods: Black-identifying participants (N = 156) enrolled in the longitudinal Pittsburgh Girls Study (PGS) provided venous blood samples before and during pregnancy to measure 25-hydroxyvitamin D (25[OH]D) levels. Participants completed questionnaires assessing sociodemographic factors, depression severity and life stress, and later reported on child behavioral and emotional problems and prosocial behavior between 2 and 4 years.

Results: Mean serum 25(OH)D concentrations were 15.5 ng/ml (s.d. = 7.7) before pregnancy and 18.0 ng/ml (s.d. = 9.2) during pregnancy; below the sufficiency threshold according to commonly used dietary guidelines. After adjusting for covariates, prenatal 25(OH)D was negatively related to behavior problems and positively related to prosocial behavior in children, although the association attenuated for behavior problems after accounting for preconception 25(OH)D, which may reflect patterns of stability. Maternal 25(OH)D was unrelated to child emotional problems, and no synergistic effects of 25(OH)D timing were observed for any child outcome.

Conclusions: Findings have relevance for Black women living in the northeast U.S. Results suggest specific associations between maternal vitamin D and positive behaviors in early childhood, regardless of sufficiency levels and suggest potential opportunities for early interventions to support healthy child development.