The role of nutrition in pregnancy course and outcome.

Much has been learned during the past several decades about the role of nutrition in the course and outcome of pregnancy. While the bulk of the data is derived from animal models, human observations are gradually accumulating. It is generally appreciated at the present time that the fetus is not a "perfect parasite"; maternal stores can be drawn upon for support but a limit exists as to the ability of the fetus to drain maternal supplies. The consequences of poor maternal nutrition range from prevention of pregnancy (through the development of amenorrhea) to the stimulation of spontaneous abortion, stillbirth and congenital malformations. Limited maternal weight gain and subsequent low birth weight is the most common result of suboptimal maternal nutrition. The impact of excessive nutrient intake during pregnancy is poorly understood at the present time. Additional work is also required to clarify the impact of toxic agents consumed by women through water, foods, or nutritional supplements.