ABSTRACT
This chapter identifies some areas of certainty and conflict in the literature on nutrition during pregnancy in healthy women. Despite several decades of study, understanding of basic nutritional processes remains somewhat limited, largely because of the inadequacy of the tools used to measure food intake, energy expenditure, and body composition. Periods of fasting might subject the fetus to erratic glucose and amino acid delivery, bouts of hypoglycemia and ketonemia, as well as inadequacies of the micronutrients needed for optimal growth and development. Obese women have a low rate of low birthweight births, even at modest weight gains. The mean birthweights of their infants are also sufficiently high, usually above 3300 g, even with maternal weight gains of only 15 to 20 lb. Little advantage is expected from further augmenting mean birthweight, even by 200-300 g. In fact, perinatal mortality may be higher in infants of obese mothers, despite higher birthweight.
