Calcium and vitamin D supplementation in pre-eclampsia: Analysis of effectiveness and safety

Purpose: To evaluate the impact of calcium and vitamin D (vit D) supplementation initiated at early pregnancy in high-risk women on reduction of preeclampsia risk. Methods: This prospective cohort study involved 492 pregnant women who had experienced pre-eclampsia or eclampsia in their current pregnancy (high risk) and were either on calcium (1000 mg/day) as well as vit D (400 IU/day) supplementation at early pregnancy or none. All the included pregnant women received standard doses of calcium (1500 mg/day) and vit D (600 IU/day) supplementation post 20 gestation weeks till childbirth. The primary outcome was pre-eclampsia characterized by hypertension as well as proteinuria. Results: From March 10, 2015 to February 24, 2018, each of the 246 pregnant women were assigned to the calcium/vit D group versus control group with no calcium/vit D. In the calcium/vit D group, 26.45 % developed preeclampsia compared to 32.11 % in control group with a Risk ratio [RR] of 0.82 (95 % confidence interval [CI], 0.62-1.08; p 0.167). No serious adverse events were related to calcium or vit D. Conclusion: Calcium/vit D supplementation during early pregnancy did not demonstrate any significant reduction in pre-eclampsia. Large, high-quality studies with higher patient numbers are needed for adequate testing of impact of calcium/vit D on pre-eclampsia.