Calcium may aid in pregnancy complications.




American Journal of Obstetrics and Gynecology

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Consumer Data: Calcium
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Calcium is the most abundant mineral in the human body. Average healthy males have about two and a half to three pounds of calcium while females have about two pounds. Approximately 99 percent of calcium is present in the bones and teeth, which leaves only about one percent in cells and body fluids. While the most important function of calcium involves the maintenance of skeletal health, the small percentage of calcium outside the bones is used to maintain a variety of vital body functions. Milk and dairy products are the major source of dietary calcium for most people. Other good sources are dark green leafy vegetables, broccoli, legumes, nuts, and whole grains.

Calcium is necessary for a wide array of other functions. Calcium may initiate muscle contractions. For this reason it plays a vital role in maintaining a healthy heartbeat. It is also involved in the body's blood clotting process. On the cellular level, calcium regulates the passage of nutrients and wastes through cell membranes. It is also involved in the regulation of various enzymes that control muscle contraction, fat digestion, and metabolism. Finally, calcium regulates the transmission of nerve impulses.

A recent study published in the American Journal of Obstetrics and Gynecology evaluated the role of calcium supplementation and the risk of pregnancy complications. Women having a daily intake of 600mg or less of calcium were recruited. Starting at gestational week 20 they were given either 1.5 grams of calcium or placebo. This study recruited 8,325 women with similar demographic characteristics, blood pressure, and gestational ages. The results showed that there was a non-significant decrease in preeclampsia in the calcium group. However, there was a reduction of severity of this condition when compared to the placebo group. In addition, preterm delivery and maternal morbidity tended to also be reduced in the calcium group. The authors concluded that, “A 1.5-g calcium/day supplement did not prevent preeclampsia but did reduce its severity, maternal morbidity, and neonatal mortality, albeit these were secondary outcomes.”1


1. Villar J, et al. World Health Organization randomized trial of calcium supplementation among low calcium intake pregnant women. Am J Obstet Gynac. Mar 2006;194(3):639-49.