Pastoralists, agropastoralists and migrants: interactions between fertility and mobility in northern Burkina Faso.

Seasonal rural to urban migration of young men is becoming an increasingly important part of the rural economy of the West African Sahel, yet little is known about how the short-term contact of men with urban centres might affect reproductive decisions and outcomes in sending areas. In northern Burkina Faso, substantial variation in short-term migration rates of young Fulani men to cities provides an opportunity to explore interactions between migration and fertility in this area. The groups most involved in seasonal labour migration experience substantially lower fertility than non-migrating groups. Fertility differentials arise largely from higher rates of secondary sterility among migrating groups, probably caused by an increased incidence of sexually transmitted diseases. Such mechanisms as changes in attitudes and knowledge regarding birth control, and the undermining of traditional practices of marriage, breastfeeding, and sexual abstinence are far less important.