Frequent reproductive cycling: does it lead to nutritional depletion of mothers?

Is frequent reproductive cycling (episodes of pregnancy and/or lactation) in poor women from developing countries a cause of poor maternal nutritional status? This review seeks to examine the evidence available to answer this question. The measurement of reproductive cycling, maternal nutritional status, and the energetic costs of pregnancy and lactation are reviewed. The data available on the anthropometric changes during pregnancy and lactation are described. Against this background, the evidence in support of the hypothesis that repeated reproductive cycling leads to a maternal depletion syndrome is examined. It is concluded that although the data are inadequate to unequivocally establish or rule out the existence of maternal nutritional depletion due to a demanding reproductive history, the data suggest this relationship does exist. Weaknesses of current measurement and study design methodologies are identified and priorities for future research aimed at clarifying the extent to which reproductive cycling affects maternal nutritional status are identified.