ENERGY REQUIREMENTS OF PREGNANCY: AN INTEGRATION OF THE LONGITUDINAL DATA FROM THE FIVE-COUNTRY STUDY

Abstract

Longitudinal data on the energy requirements of pregnant women in 5 countries--Scotland, Netherlands, Gambia, Thailand, and Philippines--indicate that the energy costs of pregnancy are about 250 MJ (60,000 kilocalories). When expressed as a proportion of the initial body weight, weight gain during pregnancy was identical for Scottish, Thai, and Philippine women. A striking finding was that Gambian women save so much energy in basal metabolism through becoming pregnant that they end up with a positive energy balance of about 46 MJ over the whole gestational period. This reflects a remarkable physiological adaptation to pregnancy in the face of severe nutritional stress. With the exception of the Thai women, energy intakes did not conform to theoretically expected quantities. In the other 4 groups, energy intakes increased overall by no more than 420 kJ/day compared with 1 MJ/day among Thai women. It remains to be determined whether Thai women are more representative of women in developing countries than Gambian or Philippine women. More studies on much larger groups of women in developing countries, with adequate prepregnancy measurements, are needed to make definitive statements about energy requirements.