Calcium supplementation reduces the risk of pregnancy‐induced hypertension in an Andes population

Summary. Previous studies have suggested that increased dietary calcium is associated with a decreased occurrence of pregnancy‐induced hypertension. In this study 106 young healthy nulliparous women, residing in Quito, Ecuador, were enrolled in a double‐blind, randomized, controlled clinical trial. From 24 weeks gestation until delivery they received either 2 g of elemental calcium per day or a placebo. Calcium supplementation was associated with a significantly decreased risk of pregnancy‐induced hypertension, with 4.1% developing pregnancy‐induced hypertension in the treatment group versus 27.9% in the placebo group. Treatment was associated with a decrease in both systolic and diastolic blood pressure over the course of pregnancy. In addition, there was a small but significant increase in serum ionized calcium levels in the calcium‐supplemented group during the treatment period.