'No Reason' to Delay Abortion Pills to Rule Out Ectopic Pregnancy

By Reuters Staff

April 15, 2022

NEW YORK (Reuters Health) — New research suggests that immediate initiation of medication-induced abortion for unwanted pregnancy is safe even before ectopic pregnancy has not been ruled out.

"This study should encourage clinicians to shift clinical practice to meet the demand of patients and facilitate an approach of 'the sooner, the better,' which is what many patients want," Dr. Alisa Goldberg of Brigham and Women's Hospital, in Boston, says in a news release.

"Our data suggest that there is no reason to mandate that patients with pregnancies of unknown location delay initiating abortion to first obtain a definitive diagnosis. In contrast, there is diagnostic and therapeutic benefit to administering abortion medications to patients with undesired pregnancy of unknown location," Dr. Goldberg adds.

The combination of mifepristone and misoprostol, commonly referred to as "abortion pills," is effective for early abortion.

Typically, before an intrauterine pregnancy is confirmed by ultrasound, women are followed with serial human chorionic gonadotropin (hCG) tests and a repeat ultrasound to rule out ectopic pregnancy.

Several studies have suggested an increased risk of ongoing pregnancy among those who initiate medication abortion before an intrauterine pregnancy is confirmed by ultrasound.

In their retrospective cohort study, Dr. Goldberg and colleagues compared the safety and efficacy of immediately starting mifepristone/misoprostol after a woman has a positive pregnancy test versus waiting to initiate treatment until a diagnosis of ectopic pregnancy has been ruled out.

Among 5,619 medication abortion visits for women with a last menstrual period of 42 days or less, 452 had pregnancy of unknown location (8.0%).

Among 432 women with no major ectopic pregnancy risk factors, same-day start of medication abortion was associated with a shorter time to diagnosis (median, 5.0 days vs. 9.0 days; = .005), with no significant difference in emergency department visits (adjusted odds ratio [aOR], 0.90;  95% CI, 0.43 to 1.88) or nonadherence with follow-up (aOR, 0.92; 95% CI, 0.39 to 2.15).

Among the 270 women who proceeded with medication abortion, same-day start was associated with a shorter time to complete abortion (median, 5.0 days vs. 19.0 days; P < .001).

However, among the 170 women with medication abortion and known outcome, same-day-start was associated with a lower rate of successful medication abortion (85.4% vs. 96.7%; P = .013) and a higher the rate of ongoing pregnancy (10.4% vs. 2.5%; = .041).

"Although uterine aspiration with inspection of the aspirate may still be the fastest and most definitive way to both terminate an intrauterine pregnancy and rule out ectopic pregnancy, health care professionals may now consider using mifepristone and misoprostol in a similar diagnostic and therapeutic way," the researchers write in Obstetrics & Gynecology.

Although there are "numerous benefits" to early initiation of medication abortion in the setting of pregnancy of unknown location, "there are also risks," they note.

"Similar to other authors, we found that initiating medication abortion in the setting of pregnancy of unknown location was associated with an increased risk of ongoing pregnancy compared with initiating medication abortion with a gestational sac visualized on ultrasonogram," they report.

"It is unclear why this occurs, although perhaps with extremely early gestations progesterone levels are not yet high enough for the effects of mifepristone to be fully realized. Nonetheless, it is important that patients with pregnancy of unknown location who take mifepristone and misoprostol have close follow-up to identify and manage ongoing pregnancies in a timely fashion," the researchers advise.

The study was supported by the Society of Family Planning Research Fund. The authors have no relevant conflicts of interest.

SOURCE: https://bit.ly/3E85FN8 Obstetrics & Gynecology, online April 7, 2022.