Professional considerations for providing mifepristone-induced abortion

Nurse Practitioner, Nov 2001 by Fielding, Stephen L, Lee, Susan S, Schaff, Eric A

Abstract

Primary care clinicians who provide comprehensive reproductive heath care can now offer patients mifepristone (Mifeprex) as an abortifacient option. Clinicians, however, must first determine if the state in which they practice has regulations specifying who can perform abortions and dispense drugs, and they must consider clinical office zoning ordinances, staffing, public relations issues, and reimbursement. This article discusses the pharmacology of mifepristone and misoprostol, professional considerations, and how to prevent and manage adverse effects and complications of medical abortion.

The recent approval of mifepristone (Mifeprex) allows primary care clinicians to provide an early abortifacient option to women. Although most training efforts are targeted to obstetricians and family physicians, advanced practice nurses (APNs) are a clinician source that can offer medical abortions in the primary care setting.

Mifepristone offers two advantages over surgical abortion. First, it provides a safe and effective alternative, enabling approximately 95% of women using this method to avoid a surgical procedure. In prior studies, most women found medical abortion to be empowering, natural, and private.1 Second, because mifepristone can be integrated into many clinicians' practices, abortion services could expand. According to the Alan Guttmacher Institute, between 1992 and 1996, the number of abortion sites declined from 2,380 to 2,042? Only 16% of counties in the United States provide abortion services, forcing many women in rural areas to travel long distances to have an abortion. Some 88% of abortions are performed within the first trimester.

Since 1990, the number of abortions in the United States has declined from 1.61 million per year to 1.37 million in 1997; two-thirds of abortions are performed in women who have not been married. An estimated 43% of American women will have had one or more abortion by age 45. Some 52% of U.S. women who have abortions are younger than age 25. Although 60% of all women who have abortions are white, black women are three times more likely and Hispanic women are two times more likely than white women to have an abortion. Of women who have abortions, 58% report using contraception during the month they became pregnant.2

Because abortion is a highly regulated, but controversial health service, APNs must consider multiple factors before seeking training to dispense mifepristone.

* Pharmacology

Mifepristone acts as a competitive blocker by binding to the receptors for progesterone. Mifepristone causes detachment of the early embryo and increases the myometrium's receptivity to prostaglandins, thereby increasing uterine contractility. Mifepristone also dilates and softens the cervix. The serum level of mifepristone peaks in about 1.5 hours and is undetectable in the serum by 11 days. Mifepristone, however, is not effective at treating ectopic pregnancies.

Misoprostol is the second required drug in the mifepristone-misoprostol regimen. Misoprostol is a synthetic prostaglandin El formulated for oral administration; the drug is currently used for preventing and treating stomach ulcers. When misoprostol is administered as part of the mifepristone-misoprostol regimen, it causes strong uterine contractions that result in pregnancy expulsion. After an oral dose of misoprostol, the serum level peaks after about 20 minutes and is metabolized rapidly during the subsequent 60 minutes.

When the oral tablets are administered vaginally, misoprostol has a delayed peak level about two-thirds as high as oral misoprostol; however, serum levels are sustained for a longer time period, leading to greater bioavailability and uterine contractility.

* Recent Mifepristone Studies

The Population Council of New York City (PC) and Abortion Rights Mobilization (ARM) sponsored separate U.S. clinical trials for mifepristone and misoprostol. The original French pharmaceutical company, Roussel-Uclaf, transferred U.S. patent rights to mifepristone without charge to the PC in 1994 because Roussel-Uclaf feared protests and boycotting by an active U.S. antiabortion lobby if they were to bring mifepristone to market. The company promised these patent rights contingent on the Clinton Administration's endorsement, which occurred shortly after President Clinton took office. The PC named a for-profit licensee, Danco Laboratories, LLC, to identify a manufacturer and market mifepristone, which was necessary for Food and Drug Administration (FDA) approval.

The PC conducted a national, multicenter clinical trial using the French mifepristone-misoprostol protocol and published its results.3 This protocol included 600 mg of oral mifepristone followed 2 days later by office-administered 400 mcg of oral misoprostol to women up to 63 days pregnant. This combination worked in 92% of women who were 49 days pregnant or less (see Figure 1). In 1996, the FDA gave preliminary clinical approval to mifepristone based on French studies, but had to wait for a U.S. manufacturer.