The effect of vitamin D supplementation on glycemic control/glucose metabolism and maternal-neonatal outcomes in women with established gestational diabetes mellitus: An updated meta-analysis.

There is increasing evidence that vitamin D supplementation may improve glycemic control and maternal-neonatal outcomes for women with gestational diabetes. It is therefore of interest that the systematic review and meta-analysis by Wang et al. [ [1] Wang M. Chen Z. Hu Y. Wang Y. Wu Y. Lian F. et al. The effects of vitamin D supplementation on glycemic control and maternal-neonatal outcomes in women with established gestational diabetes mellitus: a systematic review and meta-analysis. Clin Nutr. 2021; 40: 3148-3157 Abstract Full Text Full Text PDF PubMed Scopus (17) Google Scholar ] concluded that vitamin D supplementation during pregnancy for this population lowers fasting plasma glucose levels, fasting insulin levels and HOMA-IR while reducing risk of maternal caesarean, maternal hospitalization, newborn hyperbilirubinemia, “giant children” (macrosomia), newborn hypoglycemia, polyhydramnios and premature delivery. Unfortunately, we have concerns about the conclusions made by their review which has prompted us to revisit and update their meta-analysis.