Medical Abortion - Regimens

Regimens

The most common early first-trimester medical abortion regimens use mifepristone in combination with a prostaglandin analog (misoprostol or gemeprost) up to 63 days of gestational age, methotrexate in combination with a prostaglandin analog up to 49 days gestation, or a prostaglandin analog alone. Mifepristone–misoprostol combination regimens work faster and are more effective at later gestational ages than methotrexate–misoprostol combination regimens. Mifepristone–misoprostol and methotrexate–misoprostol combination regimens are more effective than misoprostol alone.

Medical abortion regimens using mifepristone in combination with a prostaglandin analog are the most common methods used to induce second-trimester abortions in Canada, most of Europe, China and India; in contrast to the United States where 96% of second-trimester abortions are performed surgically by dilation and evacuation.

The early first-trimester medical abortion regimen (200 mg of oral mifepristone, followed 24–48 hours later by 800 mcg of buccal misoprostol) currently used by Planned Parenthood clinics in the United States since April 2006 is 98.3% effective through 59 days gestation.

A 2011 systematic review found that it was simpler and equally safe to administer mifepristone in clinic and have the pregnant woman later take misoprostol at home as it was to administer both drugs in the clinic.