Comparing cohabiting unions and formal marriages among adolescent girls in Zambia: The role of premarital fertility and parental support

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Article (peer-reviewed)

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Purpose: In developing countries, approximately one in three girls marry before the age of 18; however, early marriage is not a homogenous experience. Cohabitation can be either a precursor or an alternative to marriage, yet studies and programs often conflate marriage types. The purpose of this study is to understand the underlying factors and stability of cohabiting and formal child marriage unions among adolescent girls. Methods: This mixed-methods study draws on four rounds of quantitative data collected annually between 2013 and 2016 as part of a longitudinal study among girls 10–19 years old in Zambia. In-depth interviews were conducted in 2017 with 32 girls, divided by formal unions and informal unions, randomly selected from the quantitative sample. Multivariate logistic models were estimated to test key associations and Cox regression models used to estimate the hazard of separation/divorce by a certain age. Results: Qualitative findings highlighted that informal unions did not typically have approval of the couples’ parents and frequently ended in separation. As compared to formal unions, having both families’ approval was associated with 69% lower odds of cohabiting (odds ratio = 0.31, p < .001), while forced entry into union due to pregnancy was associated with 61% greater odds of cohabiting (OR = 1.61, p < .05). Being in a cohabiting union was associated with a 43% greater hazard of union dissolution (hazard ratio = 1.43, p < .05). Discussion: There are key differences between formal marriages and cohabitation among adolescent girls and young women that should be considered when addressing early marriage in research and programs.