Maternal vitamin D status in relation to infant BMI growth trajectories up to 2 years of age in two prospective pregnancy cohorts

Abstract

Abstract Background Early childhood growth can affect the child's health status later in life. Maternal vitamin D status has been suggested to affect early childhood growth. However, there is a lack of studies investigating the role of maternal vitamin D status on growth trajectories during infancy. By using growth mixture modeling (GMM), maternal vitamin D status during pregnancy can be investigated in relation to different classes of infant growth trajectories. Objectives To examine the association between maternal 25‐hydroxyvitamin D (25OHD) and classes of infant body mass index (BMI) growth trajectories. Methods Mother–child pairs were included from the Norwegian Mother, Father, and Child Cohort Study (MoBa, n = 2522) and the Swedish GraviD cohort (n = 862). Maternal 25OHD in pregnancy was analyzed by liquid chromatography tandem mass spectrometry. Children's weights and heights were registry‐based. GMM identified classes of infant BMI growth trajectories up to 2 years. The association between maternal 25OHD and infant BMI class by cohort was estimated using a log‐link generalized linear model. Mixed model analysis estimated the pooled association including both cohorts. Results Two infant BMI classes were identified, stable normal and stable high. In MoBa, maternal 25OHD 75 nmol/L. In GraviD, no association was found. In pooled analysis, maternal 25OHD ≤75 nmol/L was non‐significantly associated with a higher risk of the stable high BMI growth class. Conclusions Maternal 25OHD ≤75 nmol/L may be associated with a higher class of BMI growth trajectory during infancy.

Keywords

• 25‐hydroxyvitamin D
• body mass index
• growth mixture modeling
• infancy
• latent classes
• pregnancy