Infant feeding and lactational amenorrhea in Sagamu, Nigeria.
Five hundred and twenty educated, breastfeeding women in Sagamu, Nigeria, were observed prospectively in order to describe their infant feeding practices and to determine whether any predictors of the return of menses could be identified. The women remained amenorrheic for seven months. Compared with similarly selected women in other countries, they regularly fed their infants with supplements from a very early age, yet breastfeeding frequency and duration did not decline dramatically. Semi-solid food was introduced at about four months and such supplementation, as well as earlier supplementation with milk/milk-based feedings, was associated with the return of menses. The median duration of abstinence was about four months but the mean may have been much longer. No woman became pregnant until her infant was weaned.