Association of Vitamin D supplementation in pre-eclampsia: Systematic review and meta-analysis

Abstract

INTRODUCTION: In the Philippines, hypertensive diseases of pregnancy belong in the top three causes of maternal mortality and complicate up to 10% of pregnancy worldwide. In relation with this, proper interventions must be given during the prenatal check-up to prevent occurrence that may cause feto-maternal mortality and morbidity. During prenatal check-up, pregnant women are given vitamin and mineral supplementations. Vitamin D has an association of having a risk for preeclampsia. Receptors of Vitamin D and 1-a hydroxylase are both expressed in the decidua and trophoblast cells. The active form of Vitamin D affects the transcription and function of genes associated with angiogenesis, invasion of the placenta, and normal implantation. The mechanisms mentioned are all involved in the pathophysiology of preeclampsia.OBJECTIVES: The primary outcome of this study is to determine the association of Vitamin D supplementation in preeclampsia. Specifically, this study aims to compare the following secondary outcomes: Maternal outcomes (complication of gestational diabetes mellitus and underwent cesarean delivery) and fetal outcomes (preterm delivery and birth weight).METHODOLOGY: Meta-analysis and systematic review of eight randomized controlled trials.RESULTS: Vitamin D reduced the risk of preeclampsia (risk ratio [RR] 0.45, 95% confidence interval [CI] 0.30–0.69; P = 0.0002). No significant difference on risk of gestational diabetes mellitus (RR 0.84, 95% CI 0.48–1.48) and risk of preterm delivery (RR 0.71, 95% CI 0.49–1.03). Results showed that newborns of mothers who had no Vitamin D supplementation had a higher birthweight (P = 0.010). No significant difference on cesarean section rate (RR 1.12, 95% CI 0.87–1.45).CONCLUSION: Evidence suggests that Vitamin D supplementation can reduce the risk of preeclampsia. This study encourages obstetricians in our country to add Vitamin D supplementation as prenatal medication to prevent preeclampsia, thereby reducing maternal morbidity and mortality.