Medical abortion, the use of medicines to end an early pregnancy, is up to 98% effective within the first 9 weeks of pregnancy.⁷ As a pregnancy progresses into the late first trimester, medicines are less likely to fully induce an abortion. When this happens, a follow-up surgical abortion becomes necessary to make sure that the uterus is completely clear of tissue.

• A typical treatment schedule for a medical abortion includes a first medical visit and medicine, followed 3 to 4 days later by a second medical check and medicine (another common schedule allows the second medicine to be taken at home⁸). Moderate to heavy vaginal bleeding lasts about 14 days. About 2 weeks after the second medical visit, a follow-up examination is necessary to see if you are recovering well and to make sure the procedure worked.
• Medical care before and after a medical abortion includes physical exams and lab tests, education about what to expect, self-care instructions, information on when to call your health professional, and birth control planning.

Medicines currently available in the United States for inducing abortion are:

• Misoprostol. This hormone softens and opens (dilates) the cervix and triggers uterine contractions. Misoprostol used alone may end a pregnancy but is much more effective when used with other medicines, such as mifepristone or methotrexate, in first-trimester abortions.⁹
• Mifepristone and misoprostol. Mifepristone, also known as Mifeprex or RU-486, blocks the effects of the hormone progesterone. This stops the placenta's growth, softens the cervix, and makes the uterus ready for labor. Misoprostol is then used to start contractions to clear the uterus of all tissue. This is effective 95% to 98% of the time among women 9 weeks pregnant or less.^{9, 1}
• Methotrexate and misoprostol. Methotrexate interferes with the placenta's growth; it is not as effective as mifepristone and takes longer to abort a pregnancy.⁷ Misoprostol is then used to start contractions to clear the uterus of all tissue. This is effective 95% to 99% of the time when completed before 7 weeks of pregnancy.⁷

See the section What to Think About for a comparison of medical abortion and surgical abortion.