Though a rarity in most places, polygamy is pervasive in a batch of countries situated in West and Central Africa, including Burkino Faso (36 percent), Mali (34 percent), and Nigeria (38 percent). Economist James Fenske in a 2011 paper discussing polygamy in Africa provides some shocking statistics: “Of the nearly half a million women included in the data for this study, roughly 40% who first married in 1970 share their husband today, while for women who married in 2005, that number is closer to 15%.” A crucial observation is that the percentage of women in polygamous relationships has declined; however, at 15 percent this figure is still relatively high.
As such the persistence of polygamy in Africa has attracted the attention of economists who argue that polygamy is negatively associated with development. Michèle Tertilt (2003) observes that sub-Saharan African countries where polygyny is widespread are the poorest countries in the world, with their per capita gross domestic product (GDP) being 25 percent lower than those of other countries in the region and a mere 40 percent of the GDP of other monogamous countries located in the same latitude range. The explanation is that in such societies purchasing wives is indicative of high status and moreover the families of women gain financially when their suitors pay the bride-price. Hence reliance on the bride-price as a business strategy crowds out investment.
Because under monogamous arrangements men are unlikely to pursue multiple women, they can divert more resources to productive investments, thereby boosting capital formation and economic growth. The findings of Tertilt confirm this observation: “Enforcing monogamy reduces fertility by 40%, increases savings by 35%, and raises output per person by 140%. This suggests that although the practice of polygyny is certainly not the sole cause of poverty it might be an important contributing factor for the continuing underdevelopment of Sub-Saharan Africa.”
Another pathway by which polygamy inhibits development is the cost of childrearing. Analyses show that 20.3 percent of GDP is expended on producing children in the polygamous economy, whereas only 3.5 percent of resources are devoted to childrearing in the monogamous economy. Families are usually larger in polygamous societies, so raising children is a more expensive endeavor. Some scholars also posit that polygamy can result in resource dilution considering that a greater number of adults and children are being supported on a limited budget.
Research reveals that in sub-Saharan Africa children in polygamous families are 24.4 times more likely to die when compared with children in monogamous families. Similarly, a study comparing the outcomes of children in polygamous families in Mali to their peers in monogamous families found that children in polygamous families are less likely to be enrolled in school. Furthermore, in Tanzania polygamy is a risk factor for poor nutritional status among children even when controlling for household wealth.
Perhaps a major reason for the diminished nutritional status of children in polygamous families is status inequality. First wives of polygamous husbands enjoy an elevated status and their children have access to better nutrition and are usually taller. Closer analysis of polygamy indicates that its impact on growth operates via several channels. Health is associated with productivity; therefore, the subpar nutritional status of children raised in polygamous families suggests that this is a possible channel by which polygamy impedes growth.
Secondly, polygamy has the potential to increase intrahousehold conflict. In numerous African languages, the term cowife is equivalent to jealousy. Intense competition among cowives can create a ripple effect by inducing greater sibling rivalry and stress. Joseph Henrich, Robert Boyd, and Peter J. Richerson present a wealth of information articulating the propensity of polygamous unions for conflict: “From anthropology, a review of ethnographic data from 69 non-sororal polygynous societies from around the globe reveals no case where co-wife relations could be described as harmonious, and no hint that women’s access to the means of production had any mitigating impact on conflict.”
Unsurprisingly, a 2015 review found more mental health problems, social problems, and lower academic achievement for children and adolescents from polygamous than monogamous families. Social problems resulting from polygamy reflect deadweight costs. Resources spent to correct social ills or improve the academic performance of students could have been deployed elsewhere. Due to the prominence of polygamy in Africa, there is a possibility that its negative effects are magnified on the continent.
Indeed, using the economic approach pioneered by Tertilt, Africa will be better off without polygamy. However, ceasing polygamy must be the decision of Africans. Only Africans can decide if the pleasure derived from polygamy is worth the cost of lower economic growth.