Pregnancy weight gain: still controversial

During the 20th century, recommendations for maternal weight gain in pregna ncy were controversial, ranging from rigid restriction to encouragement of ample gain. In 1990, the Institute of Medicine (IOM) recommended weight-gai n ranges with the primary goal of improving infant birth weight. These guid elines were widely adopted but not universally accepted. Critics have argue d that the IOM's recommendations are unlikely to improve perinatal outcomes and may actually increase the risk of negative consequences to both infant s and mothers. We systematically reviewed studies that examined fetal and m aternal outcomes according to the IOM's weight-gain recommendations in wome n with a normal prepregnancy weight. These studies showed that pregnancy we ight gain within the IOM's recommended ranges is associated with the best o utcome for both mothers and infants. However, weight gain in most pregnant women is not within the IOM's ranges. All of the studies reviewed were obse rvational and there is a compelling need to conduct experimental studies to examine interventional strategies to improve maternal weight gain with the objective of optimizing health outcomes.