attempted to narrow the field, confining amorphous unions within strictly defined legal and religious bounds (Guyer, 1994).
Clearly, the norms within a given society affect common behaviors that put people at risk of HIV infection as well as the messages that are most likely to alter those behaviors effectively. But it is vital to recognize that these norms are changing. In almost every society, sexual relations, reproduction, and marriage are governed by dynamic rules that will change in response to changes both in economic and demographic conditions and in the nature and course of the HIV/AIDS epidemic. In this age of increasing communication, researchers may well find that such changes are taking disparate cultures in a similar direction.
Studies on sexual behavior in sub-Saharan Africa share certain broad assumptions about the historical and social background of the study populations. Following is a brief description of the most common assumptions. Not all these reported findings are well substantiated, and many are probably too broad. However, they provide a review of current knowledge, demonstrate the diversity found, and reveal some of the complex structural issues that affect the epidemic.
It is widely believed that colonial urbanization fundamentally changed the terms of family life and gender relations in sub-Saharan Africa. The levers of this change were colonial administration and proselytizing, male migration to the cities, the creation of jobs—such as cash cropping—dominated by men, and the consequent economic marginalization of women. As taxation monetized the economy, women were forced to earn money where they could. In the indigenous cities of West Africa, they frequently did so through trading; as a result, West African women often have their own income and control their own budget without interference from their husbands. In colonial towns concentrated in East and Southern Africa, single women in town were often automatically associated with the exchange of sex for money or other support (Larson, 1989; Standing and Kisekka, 1989). Enforced migration and the search for support in a dislocated situation set the tone for multipartner relationships (Preston-Whyte, 1994).
Polygyny was common in nearly all sub-Saharan African societies and remains so, but to varying degrees (see Figure 2-1). Formal polygyny is more common in rural than in urban areas, probably because polygyny is well suited to agriculture. Nevertheless, various forms of multiple partnerships are also common in many urban areas, such as the taking of mistresses or "outside wives" (Larson, 1989; Standing and Kisekka, 1989; Hogsborg and Aaby, 1992; Carballo and Kenya, 1994; Rutenberg et al., 1994). Polygyny allows older men with resources to monopolize young women, leaving young men to search for sex outside stable unions (Caldwell et al., 1993). Junior wives may have limited access to family resources and need to supplement them by seeking outside support (Orubuloye et al., 1991). Some researchers have argued that the existence of polygyny may encourage a man to initiate a search for new wives during culturally prescribed periods of sexual abstinence following a birth to an existing wife (Larson, 1989; Orubuloye et al., 1993).