Medical abortion

medicine encyclopedia----Medical abortion

medical encyclopedia

Medical abortion

A medical abortion is a type of non-surgical abortion in which a drug is used to induce the abortion.

Medical abortion : Medical procedure

• Initial appointment, which includes pregnancy test by blood and/or ultrasound, informed consent form, and STD tests if necessary.

• An injection of methotrexate or a dose of mifepristone in tablet form.

• A prostaglandin analog--a dose of misoprostol in tablet form, or gemeprost., taken within 72 hours of the previous medication.

• A follow-up appointment to make sure the abortion was complete.

Medical abortion : Mechanism of action

Each medical abortion drug has a unique mechanism of action.

• Mifepristone binds to the progesterone receptor to block progesterone. Progesterone is necessary for pregnancy maintenance. Mifepristone also softens and dilates the cervix, and causes decidual necrosis (which leads to placental detachment). In addition, it increases prostaglandin release from the uterine lining, increases uterine contractions, and enhances uterine sensitivity to prostaglandin.

• Methotrexate blocks an enzyme necessary for DNA synthesis, thus inhibiting the growth of rapidly dividing placental trophoblastic cells.

Both mifespristone and methotrexate are followed up with a prostaglandin drug in medically approved medical abortion regimens--misoprostol or gemeprost.

• Misoprostol works by softening and dilating the cervix, and binding to myometrial cells to cause strong uterine contractions. Contractions cause expulsion of the embryo.

Misoprostol has been used alone for abortion since the 1970s. Alone, it has a higher rate of incomplete abortion than when combined with mifepristone or methotrexate. There have been reports of infections, such as toxic shock syndrome, following medical abortions, but the risk of such infection is relatively rare.

Medical abortion : Availability

In the US, medical abortion is available at women’s health care centers, private clinics, and Planned Parenthood . The price ranges from about $350 to $610, depending on which medical tests are required.

In Canada, availability is much the same, however in some provinces the procedure is fully covered by the provincial health care plan. Prices in areas where abortion is not covered by provincial health care usually range from $250 to $400.

Medical abortion : History

Mifepristone was first licensed in France in 1988. It is now approved in 29 countries, including Austria, Belgium, China, Denmark, Finland, Great Britain, Israel, Norway, Russia, South Africa, Sweden, and Taiwan. In 1993 President Clinton signed an executive order to encourage testing, licensing, and manufacturing of mifepristone in the United States. In 2000 the US Food and Drug Administration (FDA) approved the use of mifepristone for medical abortion in the United States.

It is currently possible to get mifepristone (the most common drug used in combination with a synthetic prostaglandin for medical abortion) in 60 clinics/centers in the United States.

Clinical trials of RU486 are currently being done in Canada in the cities of Edmonton, Winnipeg, Ottawa, Toronto, Montreal, Halifax and St. John's Newfoundland. The drug cannot be imported for personal use. However, medical abortions using Methotrexate and Misoprostol are available in Canada.