The diet of pregnant women has been restricted in various ways since earliest history. Dietary restriction may have severely deleterious effects on the fetus. Our study revealed a positive correlation of prepregnancy weight and pregnancy weight gain to term infant birthweight. Their influences are independent and additive. It is of the utmost importance to the fetus and the future of the human race that the diet of pregnant women contain the caloric value and essential nutrients recommended by the National Research Council.