The risk of morbidities in newborns of antenatal vitamin D supplemented gestational diabetes mellitus patients

BACKGROUND: There is no established antenatal intervention that reduces the risk of preeclampsia and preterm delivery in gestational diabetes mellitus (GDM) mothers and hyperbilirubinemia, hypoglycemia, and hospitalization in their newborns. Henceforth, this study aims to study how these risks change on prenatal vitamin D supplementation. METHODS: Randomized parallel arm trials comparing these interventions’ effect on the above outcomes were searched in the PubMed, Embase, and Scopus, irrespective date, and language of publication. Each eligible trial’s risk of bias was assessed using the Cochrane collaboration tool. Using random-effects meta-analysis, the risk of the outcomes was compared. RESULTS: Six eligible Iran-based trials of about 476 participants were included in this review. Four trials complemented vitamin D along with other nutrients. Overall, the risk of bias was low in these trials. The newborns of antenatal vitamin D recipients have a reduced risk of hyperbilirubinemia (relative risk [RR] = 0.46; 95% confidence interval [CI]: 0.33, 0.64; I(2) = 0%) and hospitalization (RR = 0.46; 95% CI: 0.32, 0.65; I(2) = 0%) than those who did not receive the supplement. The rest of the outcomes did not vary between the compared interventions. The results remained unchanged on using a fixed-effect meta-analysis, repeating the meta-analysis while eliminating a trial each time, and on imputation analysis. An auxiliary meta-analysis comparing the intervention with placebo also suggested a decreased risk of hyperbilirubinemia (RR = 0.43; 95% CI: 0.30, 0.62; I(2) = 0%) and hospitalization (RR = 0.44; 95% CI: 0.30, 0.62; I(2) = 0%). CONCLUSION: Newborns of GDM mothers who received vitamin D as a sole or co-supplement antenatally have a decreased risk of hyperbilirubinemia and hospitalization.