Declining risk of surgical intervention following early medical abortion: A time trend analysis

OBJECTIVE: To evaluate the time trend in risk of surgical intervention following early medical abortion.

STUDY DESIGN: We conducted a retrospective observational study including all medical abortions induced before a gestational age of 63 days during the period 2008-2012 in a Danish gynecology clinic with a single provider deciding the necessity of subsequent surgical intervention. All included abortions were followed for 8 weeks from first medical administration. We extracted information on surgical intervention during follow-up and potential confounding variables from local and national health registers and assessed these according to calendar time. Multiple logistic regression provided an adjusted odds ratio of the association between calendar time and risk of surgical intervention.

RESULTS: A total of 1372 abortions were induced on site during the study period. Surgical interventions on site decreased from 10.2% in 2008 to 2.6% in 2012 (p < 0.001). The decline was significant after adjustment of gestational age, maternal age, and reproductive history, odds ratio for 1-year increase 0.71 (95% CI: 0.59-0.86).

CONCLUSION: Risk of surgical intervention following early medical abortion declined by time independent of known risk factors for surgical intervention in a setting with a single provider deciding the necessity of surgical intervention.

IMPLICATIONS: Risk of surgical intervention following early medical abortion declined over time during a period without procedure changes and with no variations in known determinants of surgical intervention. This finding may indicate the effect of increasing provider experience in the reduction of risk of surgical intervention following early medical abortion.