Medical abortion with mifepristone and vaginal misoprostol between 64 and 70 days' gestation

Hisa J

Lohr P

Taylor J

Creinin M

Contraception
May 2019

Objective

To evaluate outcomes with mifepristone 200 mg orally followed 24–48 h later by misoprostol 800 mcg vaginally for medical abortion at 64–70 days of gestation.

Study design

We reviewed electronic databases and medical records for medical abortion cases at 64–70 days' gestation at British Pregnancy Advisory Service clinics in England and Wales from May 2015 through October 2016. Women selected in-office follow-up or self-evaluation of abortion outcome using a checklist along with low-sensitivity urine pregnancy testing. We excluded cases in which we could not locate records and when women did not proceed with medical abortion, did not use misoprostol following mifepristone if abortion had not occurred and did not attend a scheduled follow-up assessment. We analyzed demographic characteristics, treatment outcomes and significant adverse events. We defined treatment success as complete abortion without surgical evacuation and without continuing pregnancy.

Results

Of 2743 cases identified, we could not locate 40 charts and excluded 30 cases, leaving a final sample of 2673. Overall, 2538 (94.9%, 95% CI 94.1–95.8) women had a successful medical abortion. Reasons for failure included continuing pregnancy (n=90, 3.4%, 95% CI 2.7–4.1), retained nonviable pregnancy (n=2, 0.1%, 95% CI 0–0.2) and incomplete abortion (n=43, 1.6%, 95% CI 1.1–2.1). Of those with continuing pregnancies, 81 underwent a uterine aspiration and 9 opted to continue the pregnancy. Thirty-five (1.3%, 95% CI 0.9–1.7) women had significant adverse events; 16 (0.6%, 95% CI 0.3–0.9) underwent an in-hospital aspiration. Pelvic infection (n=4, 0.2%) and transfusion (n=1, 0.03%) occurred rarely.

Conclusion

Medical abortion from 64 to 70 days with mifepristone and vaginal misoprostol is effective with a low rate of serious adverse events.

Implications

Medical abortion between 64 and 70 days of gestation may be offered on an outpatient basis using mifepristone and vaginal misoprostol. Service provision without an in-person follow-up is feasible. Not all women with a continuing pregnancy after medical abortion treatment opt to have an aspiration procedure.