High protein supplementation in pregnancy

To assess the effects of providing pregnant women with high-protein nutritional supplements on gestational weight gain and on the outcome of pregnancy, including fetal growth, gestational duration, and maternal and fetal/infant morbidity and mortality.

The register of clinical trials maintained and updated by the Cochrane Pregnancy and Childbirth Group.

All acceptably controlled comparisons of protein/energy supplementation in which the protein content of the supplement provided >25% of its total energy content.

Data were extracted by the author from published reports, and supplemented by additional information from trialists contacted by the author.

Two studies involving 1076 women were included. High protein supplementation was associated with a small, statistically nonsignificant increase in weekly maternal weight gain. The two available trials provide no evidence of benefit on fetal growth; indeed, the adjusted mean difference in birth weight is -58. 4 g. One trial also reported a nonsignificantly increased risk of neonatal death with high-protein supplementation.

There is not enough evidence to evaluate the use of high protein supplementation in pregnancy.