Angela Y. Chen

Relationship of outcomes of methotrexate/misoprostol abortion to prior pregnancy experience∗

Objective: Prior pregnancy has been associated with increased rates of suction curettage in previous analysis of early medical abortion using methotrexate and misoprostol (P <0.004). However, neither the mechanism nor the contribution of subgroups to outcome differences has been clarified. Methods: Information from 1,973 patients in a multicenter case series of women undergoing abortion with methotrexate and misoprostol at 49 days or less was used. We used χ2 statistics and logistic regression (SAS, Inc.); P <0.05 was considered significant. Results: Suction curettage rates ranged from 9.6% to 17.7%; the lowest rate (9.6%) was among never-pregnant women. Women with prior abortion, but no prior births, had higher rates of curettage than never-pregnant women (12.1%). Women with prior induced abortion only (n = 412) had rates of curettage of 11.4%, and women with prior spontaneous abortion only (n = 31) had rates of 12.9% (NS). Women with prior birth had the highest rates of suction curettage (15.6%). Women with prior vaginal birth only (n = 767) had rates of curettage of 15.0%, whereas women with prior abdominal deliveries only (n = 113) had rates of 17.7% (NS). Curettage and parity (para 1, 14.4%; para 2, 16.4%; para 3, 14%; para 4, 10%) did not show a trend with increasing parity. Conclusion: The observed increase in curettage with prior pregnancy and birth compared with never-pregnant women does not appear to be influenced by mode of delivery, cause of abortion, or increasing parity.