Clinical Question

Is same-day initiation of medication abortion safe and effective for early pregnancy of unknown location?

Bottom Line

The retrospective cohort study suggests that the same-day start of medication abortion is a reasonable option for more rapid pregnancy termination and exclusion of ectopic pregnancy for patients who had their last menstrual period within 42 days and initial ultrasonography results showing no gestational sac. Patients with major risk factors for or symptoms suggesting ectopic pregnancy were not eligible for same-day medication abortion. A larger randomized controlled trial is necessary to verify the relative effectiveness and safety of same-day initiation of medication abortion vs. delaying it until the diagnosis of intrauterine pregnancy. (Level of Evidence = 2b)

Synopsis

The study is a retrospective cohort of 452 patients with a positive pregnancy test result seeking medication abortion within 42 days of their last menstrual period. Initial ultrasonography showed no gestational sac (intrauterine or ectopic). Those with major risk factors for ectopic pregnancy (e.g., intrauterine device in situ, prior tubal surgery, prior ectopic pregnancy) were not eligible for same-day treatment and were excluded from the study. Of the study cohort, 55 (12%) had initial hCG testing and received same-day start of medication abortion at the discretion of the treating clinician using mifepristone, 200 mg orally, followed by misoprostol, 800 mcg orally within 48 hours, and serial quantitative human chorionic gonadotropin (hCG) testing. The remaining patients had hCG testing and were not treated until intrauterine or ectopic pregnancy was determined (i.e., delay-for-diagnosis group).

Initial hCG results were received after medication administration. If the hCG level was less than 2,000 mIU per mL (2,000 IU per L), medication abortion could proceed as planned. An hCG level from 2,000 to 2,999 mIU per mL (2,000 to 2,999 IU per L) required repeat ultrasonography on the same day as results were received. If the hCG level was 3,000 mIU per mL (3,000 IU per L) or greater, the patient was referred to the emergency department for further evaluation to exclude ectopic pregnancy. The rate of ectopic pregnancy was 31 out of 452 patients (6.9%; 95% CI, 4.7 to 9.6), 25 of whom presented with symptoms of ectopic pregnancy at initial evaluation, all of which were in the delay-for-diagnosis group. Among the rest of the delay-for-diagnosis group, 161 patients (40.9%) proceeded with the medication abortion regimen and 62 (15.7%) were switched to uterine aspiration.

The primary outcome of median time to diagnosis of pregnancy location was five days in the same-day-treatment group and nine days in the delay-for-diagnosis group (P = .005). In the delay-for-diagnosis group, there were nine (2.4%) patients with adverse events (e.g., ruptured ectopic pregnancy, hemorrhage of more than 500 mL, blood transfusion, hospital admission), compared with zero in the same-day treatment group. The analysis of medication abortion effectiveness included only the 170 patients who received it and had known pregnancy outcomes. Successful abortion, defined as at least a 50% decrease in serum hCG level 48 to 72 hours after taking mifepristone or an 80% decrease one week after taking misoprostol, was lower in the same-day treatment group (85% vs. 97%; P = .013) and the rate of ongoing pregnancy was higher (10% vs. 3%; P = .041). Nonadherence to follow-up did not differ between groups.

Study design: Cohort (retrospective)

Funding source: Foundation

Setting: Outpatient (any)

Reference: Goldberg AB, Fulcher IR, Fortin J, et al. Mifepristone and misoprostol for undesired pregnancy of unknown location. Obstet Gynecol. 2022:139(5):771-780.

Editor's Note: We strive to provide the best available evidence to counsel patients presenting with an undesired pregnancy, but recognize this is a controversial topic.—Sumi Sexton, MD, Editor-in Chief