Data from the World Fertility Survey and the Demographic and Health Survey are used to analyze differences in infertility in Cameroon and Nigeria. It was assumed that specific patterns of behaviour are associated with higher infertility and that women's lives are greatly affected by their ability to reproduce. Both hypotheses are supported by multivariate analysis. Odds of being infertile were significantly higher for women who became sexually active in their teens, and those of having been married several times or of being currently unmarried are higher for infertile women. The patterns of infertility vary substantially within both Cameroon and Nigeria, but are very similar in the two countries. The most striking difference is that the incidence of infertility became less variable during the 1980s between different groups in Cameroon, but more diverse in Nigeria. Differences in the latter country are also more age-dependent than in the former.