Antihypertensive medications are always the last option for blood pressure control in pregnant patients. This article gives an insight into the use of calcium supplementation to prevent hypertension in these patients. This study is a double blinded, randomized controlled trial. The study shows hypertensive disorders of pregnancy were lower in the calcium group than placebo. The risk of both gestational hypertension and preeclampsia were also lower in the calcium group. Most importantly, the mechanisms involved in lowering blood pressure in pregnant females receiving calcium supplementation are not well understood. The article discusses the possible mechanisms involved.