Weight changes during pregnancy and the postpartum period.

Weight gain during pregnancy is considered a major determinant of fetal growth. Low maternal weight gain is associated with an increased incidence of low birth weight infants who are at higher risk for increased mortality. For the past twenty years, weight gain recommendations have been centered around one value (11 kg) as representative of a weight gain objective. Newer recommendations are based on what is considered optimal infant outcomes and not necessarily on maternal health considerations. These recent recommendations indicate the importance of pregravid weight in setting weight gain goals with overweight gravida advised to gain less than normal weight or underweight gravida. When confounding variables are controlled, maternal weight gain is similar in adolescents and older women. Reports on weight loss during the postpartum period indicate a high degree of variability in total weight change. In general, with current levels of weight gain, each successive birth adds about 1 kg of body weight above that normally gained with age. There is very little evidence to suggest that breast feeding as compared to other methods of infant feeding, causes body weight to return to prepregnancy levels at a faster rate.