Maternal nutritional status is inversely associated with lactational amenorrhea in Sub-Saharan Africa: results from demographic and health surveys II and III.

Breast-feeding is positively associated with the duration of postpartum amenorrhea; thus it is a major determinant of fertility in countries where effective contraceptive methods are not widely available. The objective of these analyses was to examine the association between maternal nutritional status and lactational amenorrhea (LA) among breast-feeding women. Women who were not pregnant, who were breast-feeding, who were not using hormonal contraceptives and who had a child </=2 y old at the time of survey were included in the analyses. Multivariate logistic regression was used to examine this association with the use of Demographic and Health Surveys data collected in seven Sub-Saharan African countries between 1990 and 1994. Analyses were adjusted for nine confounders, including breast-feeding behavior, child nutritional status and child age. Within-country analyses consistently showed the trend of low maternal body mass index (BMI) associated with a higher likelihood of being amenorrheic. Pooled analyses (n = 9839) were performed using two child age groups (<9 mo and 9-24 mo). The <9 mo pooled analysis showed that women with BMI < 18.5 kg/m2 (odds ratio; 95% confidence interval: 1.6; 1.2-2.3) were more likely to remain amenorrheic at the time of the survey than their "better-nourished" counterparts. The 9-24 mo pooled analysis showed that the differential probability of being amenorrheic between undernourished and "better-nourished" women increased with time postpartum, where the adjusted difference in the median duration of amenorrhea associated with maternal nutritional status among breast-feeding women was 1.4 mo. These results suggest that maternal nutritional status plays an independent role in the return of ovulation after delivery.