Dietary protein and human pregnancy performance.

Low birth weight is an important predictor of neonatal mortality and morbidity. Women of low socioeconomic classes give birth to disproportionate numbers of low-birth-weight infants and eat poorer diets than those of higher classes. Although maternal weight gain in pregnancy is positively associated with birth weight, and although animal studies demonstrate the important effects of protein restricti-n on reproductive performance, the significance or lack thereof of diet in general and of protein intake in particular in pregnant women in generally well-nourished populations has not been established. The conflicting data on human pregnancy performance and diet are critically reviewed.