The relationship between cumulative number of cohabiting partners and number of children for men and women in modern Sweden

Societies with institutional monogamy may be effectively polygynous through some males having several wives in succession: serial monogamy. This study investigates the relationship between the number of cohabiting partners and the number of children in a modern society where serial monogamy is common in both sexes. Data from an investigation on cohabitation and reproduction were provided by the Swedish Statistics Bureau, where the oldest cohort were used to estimated “lifetime” number of partners and children. The analyses were repeated for the next-to-oldest cohort. About 78% males and 79% females had one partner, and about 15% of both sexes had more than one partner during their reproductive lifespan in the oldest cohort. Thus, monogamy was predominant, and serial monogamy was equally common among men and women. Serial monogamy was somewhat more frequent in the next-to-oldest cohort. Remating increased the number of offspring for males, but not for females, in both cohorts. This is in accordance with the idea of serial monogamy being a conditional reproductive strategy for males in a society with institutional monogamy. However, the reproductive costs and benefits for females of remating are obscure. In the oldest cohort of males there were significantly more unskilled laborers with no partner and no children compared to other socioeconomic categories. The same pattern, however nonsignificant, was found for the next-to-oldest cohort and, according to SSB data, is strong when even younger age groups are included. Data on socioeconomic status for females were not provided.