Labor-saving technology and fertility increase in rural Africa.

Abstract

Across the developing world, labor-saving technologies have been designed and implemented to introduce savings in the time and energy that women allocate to work. In rural Arsi, southern Ethiopia, a recent water-supply scheme has reduced long arduous trips to obtain water and is associated with considerable improvements in women’s energy budgets. Assuming that the time and energy saved is not diverted to other energetically costly activities and nutritional levels remain constant, evolutionary life-history theory predicts that this energy may be diverted into reproductive effort and thus may increase fertility. The aims of this bio-demographic study are to detect any effects of the installation of village water taps on birth spacing and women’s overall energetic status. Field studies in human reproductive ecology have revealed that fertility is responsive to changes in maternal condition (Hill and Hurtado 1996, Tracer 1991). Other clinical trials have identified the physiological pathways along which energetic factors influence reproductive function (Ellison 2001). A negative energy balance, attributed to the combined effect of seasonal high workloads and low nutritional reserves, is associated with reduced fecundity (Bailey et al. 1992, Ellison, Peacock, and Lager 1989, Panter-Brick, Lotstein, and Ellison 1993). Although the effects of short-term seasonal alteration in energy levels have been explored, the effect of long-term changes under conditions of poor nutrition is less well understood. The proposed study is the first to investigate whether physiological changes associated with workload affect fertility at a population level—that is, translate