Vitamin D Status Impacts Inflammation and Risk of Infections During Pregnancy

Archived serum collected from 158 adolescents at mid-gestation (approximately 26 weeks) and delivery will be analyzed for inflammatory cytokines. The impact of these inflammatory markers will be assessed by comparing the data to measures of vitamin D (25(OH)D, calcitriol and parathyroid hormone) and infections and inflammatory complications abstracted from medical charts. Placental samples were collected from a subset (n=132) of these pregnant teens and these tissues will be analyzed using genome wide microarray of messenger ribonucleic acid (mRNA) and microRNA (miRNA) related to inflammatory processes. A separate group of pregnant adolescents (n=140) will be recruited at entry into prenatal care for a vitamin D supplementation trial. Teens will be randomly assigned to one of two supplements (200 IU D3/d vs. 2000 IU D3/d). Similar to the retrospective analysis, maternal calciotropic hormones and inflammatory cytokines will be assessed at entry into the study, mid-gestation (23-28 weeks) and at delivery. Inflammatory processes and infections reported across pregnancy will be evaluated in relation to vitamin D status and inflammatory markers.