Influence of smoking, weight gain, and pregravid weight for height on intrauterine growth

Abstract

Combined effects of pregravid weight, weight gain and smoking on birth weight, length, and head circumference was investigated in uncomplicated, term pregnancies. Each gravida was categorized by height and pregravid weight as underweight, normal, moderately overweight, or massively overweight. Weight gain was grouped: poor, low-normal, high-normal, and excessive. Women who smoked 10 to 20 cigarettes daily were studied. Women who did not smoke were used as controls. Birth weights, lengths, and head circumferences were evaluated. Within each pregravid category and each gain group there was nearly uniform incremental increase in mean birthweight with advancing weight gain in both smoking and nonsmoking women. Infants born to smoking women fell behind nonsmoking counterparts by an entire gain group regardless of the mother's pregravid classification. Similar trends were observed in length and head circumference, although not as pronounced. Encouragement of higher weight gains helps correct the growth retardation observed in infants born to women who smoke.