Nutritional Status and the Risk of Preterm Birth

Abstract

A woman’s body mass index and nutritional status should be assessed in the antenatal period. The evidence indicates that maternal anemia is a risk factor for preterm birth. Ensuring adequate levels of iron and folic acid is essential for general pregnancy health and outcomes. To reduce the risk of pre-eclampsia, daily calcium supplementation for populations with low dietary calcium intake may be advised, although negative interactions between iron and calcium supplements may occur so these two nutrients should be administered several hours apart. In undernourished populations, balanced energy and protein supplementation should also be recommended for pregnant women (though not specifically linked to a reduction in preterm birth). For populations at risk of vitamin D deficiency, possible benefits for general pregnancy outcomes may be gained from vitamin D supplementation. Where dietary zinc is low, it has been suggested that zinc supplementation may reduce the risk of preterm birth. However, further research is required to clarify the benefits of supplementation. For example, vitamin D in combination with calcium may increase the risk of preterm birth. In the antenatal period, the most important focus should be on promoting a good quality diet in general, rather than a specific supplementation regime.