Objectives To estimate the impact in the number of incident abortions due to the Dobbs v Jackson decision.

Methods We fit an interrupted time series model to annual incident abortions from 2004 to 2023 in the state of Colorado. In addition, we computed the proportion of residents that received abortive care from outside Colorado before and after the Dobbs v Jackson decision. Finally, we estimated the proportion of abortions over time stratified by gestation week of the mother.

Results We found that in the state of Colorado, after Dobbs v Jackson (compared to before): (1) an increase in non-resident incident abortions immediately after the decision (2) which is driven by residents in the states surrounding Colorado with the most restrictive abortion laws; the uptick in non-resident abortions has likely led to longer wait times, a higher burden on facilities, and (3) later gestation times for the mother.

Conclusions Shifts in abortion patterns in Colorado is evidence that the ramifications of Dobbs v Jackson extend beyond individual state borders, impacting both state-residents and non-residents seeking care. Policymakers must consider these findings in future reproductive legislation to ensure access to abortion in protective states, such as Colorado.

Public health implications This work underscores the immediate impact of healthcare legislation and the increased burden on healthcare services for states with more permissible abortion legislation.

The authors have declared no competing interest.

This study did not receive any funding.

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