Research led by epidemiology and biostatistics assistant professor, Dr. Nansi Boghossian (University of South Carolina, Arnold School of Public Health) has found an association between maternal vitamin D deficiency and lower bone density/smaller size at birth. The study was published in the European Journal of Clinical Nutrition.
Observational research has linked maternal vitamin D status with fetal growth and offspring’s bone mass. In this study, Dr. Boghossian and her collaborators analyzed longitudinal measures of maternal vitamin D and neonatal body composition using three pregnancy samples from the Memphis site of the 1992-1995 Calcium for Preeclampsia Prevention Trial.
The researchers characterized the trajectory of total maternal serum 25-hydroxyvitamin D concentration by race and examined whether vitamin D status is associated with neonatal anthropometry and body composition as assessed by dual energy X-ray absorptiometry. They tested racial differences using an interaction term between blood draw gestational week and race in linear mixed-effects models. Linear regression and linear mixed-effects models estimated the adjusted associations between total vitamin D concentration with neonatal anthropometry and body composition including interactions with infant sex and serum calcium.
Dr. Boghossian and her team found that total vitamin D concentration increased with gestational age; however, its trajectory over pregnancy did not differ between African-American and Caucasian women. Deficient maternal vitamin concentration was associated with lower neonatal total bone mineral density. Among male newborns, deficiency was also associated with lower lean mass and birthweight. Further, deficient maternal vitamin D was associated with lower ponderal index among those in the lowest calcium tertile.
The authors concluded that vitamin D deficiency during pregnancy is associated with lower bone density and smaller size at birth in certain subgroups. These findings suggest the importance of maternal vitamin D status in fetal development.