Persistent inequalities in adolescent motherhood in Peru (1981–2017): From wide approaches to intercategorical mapping

Adolescent motherhood in Peru has declined over the past four decades; however, pronounced socioeconomic disparities persist. Drawing on microdata from the 1981, 1993, 2007, and 2017 population censuses-which contain sample sizes more than two orders of magnitude larger than those of Demographic and Health Surveys (DHS)-this study examines the long-run evolution of inequalities in adolescent motherhood. We employ relative risk measures, concentration indices, and their decompositions. We also apply a descriptive intercategorical approach that identifies small, multiply disadvantaged groups, a methodology feasible only with large amounts of data, such as census microdata. National prevalence decreased from 15.4% in 1993 to 11.5% in 2017; nonetheless, the risk ratio between adolescents in the poorest and richest wealth quintiles remained strikingly high. The concentration index (CI) declined between 1981 and 2007; however, this trend reversed after 2007. Decomposition analysis shows that between 1981 and 2007, the main factor statistically contributing to inequality was education level, accounting for approximately one-third of the total CI. Finally, the intercategorical mapping reveals that in 2017, three groups jointly defined by wealth, education, ethnicity, region, and rurality continued to face adolescent motherhood rates of 43%, levels that have remained virtually unchanged since 1993.