CLINICAL QUESTION

Does calcium supplementation during pregnancy improve maternal and infant outcomes, other than preventing hypertensive disorders of pregnancy?

EVIDENCE-BASED ANSWER

Calcium supplementation may slightly reduce preterm birth rates between 34 and 37 weeks' gestation, but it likely has little to no effect on preterm birth rates less than 34 weeks' gestation or on the risk of low birth weight (less than 2,500 g).¹ (Strength of Recommendation: B, inconsistent or limited-quality patient-oriented evidence.)

PRACTICE POINTERS

Maternal nutrition during pregnancy has significant effects on fetal growth and development.¹ The World Health Organization (WHO) recommends up to 2,000 mg of daily calcium supplementation, particularly in pregnant women with low dietary calcium intake, to reduce the risk of hypertensive disorders in pregnancy.^2,3 Recent studies showed that less than 1,000 mg of daily calcium supplementation was also effective.^4,5 However, the effect of calcium supplementation on other maternal and infant outcomes remains uncertain. The authors of this Cochrane review aimed to identify whether antepartum calcium supplementation reduces preterm birth and low birth weight risk.¹