Energy requirements of pregnancy in The Gambia.

At most times of the year adjustments in maternal energy expenditure and energy balance in rural Gambian women can provide sufficient energy to sustain reasonable rates of fetal growth without an increase in food intake, although this study suggests that the overall level of energy intake has been substantially underestimated in the past. At certain times of year, however, pre-harvest food shortages and the energy demands of subsistence farming did substantially reduce maternal fat stores and fetal growth. Dietary supplementation, already known to increase birthweight, also had measurable effects on the mothers' physiology, resulting in increased energy expenditure on basal metabolism and improving maternal fat deposition. These findings suggest that the precise energy cost of pregnancy varies as a function of the additional energy intake consumed at this crucial period.