Comparison of medication abortion outcomes at less than and greater than 6 weeks gestation

Abstract

ObjectivesTo compare outcomes and characteristics of two cohorts of patients: those receiving medication abortion (MAB) at ≤42 days gestation and those at 43-56 days gestation. Study DesignWe conducted a retrospective cohort study to compare characteristics and outcomes of all 142 patients accessing MAB at ≤42 days versus 200 patients at 43-56 days in 2022. We sought to detect a 7% difference in MAB success with 80% power and an alpha of 0.05. We compared follow-up responses and unscheduled contacts with the healthcare system. ResultsAbortion success rates were similar between the ≤42 day and 43-56 day groups (94.3% vs 97%, p=0.226). Those ≤42 days had a higher frequency of unscheduled office visits (13% vs 6%, p=0.01) but no difference in phone calls or emergency room visits. More patients with successful MAB in the ≤42 days group answered that bleeding (11.7% vs 1.9%, p=0.006) and cramping (10.5% vs 2.9%, p=0.035) were not heavier or worse than a period, and that they did not have pregnancy symptoms prior to the abortion (15.8% vs 6.0%, p=0.034).Patients ≤42 days gestation less often had a pre-treatment ultrasound (48% vs 64%, p=0.004). Patients without prior ultrasound more often needed uterine aspiration to complete the abortion (6.8% vs 2%, p=0.027). ConclusionsPatients undergoing MAB at ≤42 days have similar success rates but more unscheduled office visits, and more ambiguous symptoms when using standardized questions for evaluating abortion success. Clinicians should consider adapting their anticipatory guidance and counseling for this population. ImplicationsAccess to very early abortion is increasingly relevant as legal restrictions on abortion increase. Earlier gestations may have different responses to standard follow-up questions despite a successful MAB and may have more interactions with the healthcare system.