Decline in Induced Abortion Rates in Spain 2011-2021: Compositional or Behavioral Effect?

Mikolaj Stanek, University of Salamanca
Miguel Requena, Universidad Nacional de Educación a Distancia (UNED)

This study examines how shifts in population composition and behavioral changes among sociodemographic groups influenced abortion rates in Spain from 2011 to 2021. Using data from the Voluntary Terminations of Pregnancies register and Spanish Population and Housing Censuses, we analyzed abortion rates among women aged 12–52. Poisson regression models and the Oaxaca–Blinder decomposition technique were employed to assess the impact of demographic shifts and behavioral variations on abortion trends. Our findings indicate that 40% of the decline in abortion rates is attributable to changes in sociodemographic composition. Specifically, a decrease in the proportion of younger women and an increase in educational attainment significantly contributed to this decline, though the rising number of immigrant women partially offset this trend. The remaining decline, not explained by these factors, is linked to behavioral changes. Significant reductions in the likelihood of abortion were observed among women under 35, immigrants from non-high-income countries, and those with lower education levels. This study reveals that behavioral changes are not uniform across groups. The largest reductions occurred in the subgroups with initially higher abortion rates, leading to a narrowing of disparities by age, education, and migration background.

Keywords: Sexual and Reproductive Health and Rights, Decomposition analysis, Migrant Populations and Refugees

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