Background and objective: Insufficient vitamin D status (25OHD; 25-hydroxyvitamin D) during pregnancy is suggested to increase the risk of pregnancy complications and adverse neonatal outcomes. Vitamin D insufficiency during pregnancy has also been associated with unfavourable childhood growth and cardiometabolic health, but evidence is scarce. The aim of this study was to investigate the association between maternal vitamin D status in pregnancy and markers of childhood cardiometabolic risk.
Methods: This study is based on a subset of 244 mother-child pairs from the Norwegian Mother, Father and Child Cohort Study (MoBa). Maternal blood was drawn in mean gestational week 18.5 for analysis of 25OHD. Median (range) child age was 10 (7-12) years. Children´s weight, height, and waist circumference were reported by the parents. A non-fasting blood sample was drawn from all children and z-scores were calculated for all outcomes. The associations were studied using linear regressions, adjusted for maternal BMI, education and origin, and child’s sex and age. Outcomes of blood lipids were additionally adjusted for child’s BMI.
Results: Overall, median (25th-75th percentiles) 25OHD concentration during pregnancy was 52.5 (40-65) nmol/L and 11% of children were classified as having overweight. Median childhood plasma HDL was 1.6 mmol/L, LDL was 2.5 mmol/L, total cholesterol was 4.5 mmol/L, and triglycerides were 0.8 mmol/L. Higher maternal 25OHD concentration was associated with 0.067 higher childhood adiponectin z-score (p=0.039) but not with BMI, blood lipids, or leptin z-scores. There was an interaction with maternal pre-pregnancy BMI in the association between maternal 25OHD and childhood waist circumference (p=0.105). In children of mothers with pre-pregnancy BMI <25 kg/m2, higher maternal 25OHD and was associated with 0.062 lower childhood waist circumference (p=0.031).
Discussion: Higher vitamin D status during pregnancy may be associated with higher adiponectin z-score and lower waist circumference z-score in childhood.