Quantifying the impact of targeted regulation of abortion provider laws on US abortion rates: a multi-state assessment


OBJECTIVES: In this paper, we estimate the average effect of two common TRAP (targeted regulation of abortion providers) laws on abortion rates using a novel longitudinal database of state-level policy shifts. STUDY DESIGN: We merged several sources of policy, abortion, and sociodemographic data from 1991-2014. We used a difference-in-differences design to control for time-fixed state-level characteristics and common factors affecting abortion trends across all states, as well as measured time-varying state-level factors that may impact TRAP enforcement and abortion rates. We used generalized linear models with cluster-robust standard errors to obtain our estimates. RESULTS: Enforcement of ambulatory surgical center (ASC) laws reduced the abortion rate by 1.25 abortions per 1000 women aged 15-44 (95% CI: -3.39, .89), and admitting privilege laws increased the abortion rate by .57 abortions per 1000 women aged 15-44 (95% CI: -.68, 1.83), but neither effect was statistically distinguishable from zero. Our findings were robust to the inclusion of covariates and various sensitivity analyses. CONCLUSION: Our results suggest that ASC and admitting privilege laws did not, on average, lead to a meaningful change in abortion rates. IMPLICATIONS: US abortion rates are currently at record lows, but our findings suggest that TRAP laws are not a meaningful driver of this trend. However, this does not mean that these laws are without consequence in a particular state (or a given year). Researchers should assess the average long-run impact of TRAP laws on other outcomes in the future.

Sam Harper
Sam Harper
Associate Professor of Epidemiology

My research interests include impact evaluation, reproducible research, and social epidemiology.