Premarital Births and Union Formation in Rural South Africa.

Context: In rural South Africa, women often delay union formation until they are in their late 20s, though premarital first births are common.

Methods: Longitudinal data from the Agincourt Health and Socio-Demographic Surveillance System in rural South Africa were used to examine the relationship between premarital birth and union entry among 55,158 nonmigrant women aged 10-35 who took part in at least one annual census from 1993 to 2012. Discrete-time event history models were used to determine whether the likelihood of union formation differed between women who had had a premarital first birth and those who had not. Associations between single motherhood and union type (marriages or nonmarital partnerships) were identified using logistic regression.

Results: Forty-five percent of women had had a premarital first birth and 25% had entered a first union. Women who had had a premarital first birth were less likely than other women to have entered a first union (odds ratio, 0.6). Women who had had a premarital birth in the past year were more likely than those without a premarital birth to have entered a union (1.5), but women had reduced odds of union formation if they had had a birth 1-2 years earlier (0.9) or at least five years earlier (0.8). Unions formed within two years of a premarital birth had an elevated likelihood of being nonmarital partnerships (1.2-1.4).

Conclusions: Single motherhood is common in the Agincourt HDSS, and women with a premarital first birth face challenges in establishing committed unions with partners.