The FDA in 2000 approved mifepristone to terminate pregnancies of up to 10 weeks, when used with a second drug, misoprostol. Mifepristone is taken first to dilate the cervix and block the hormone progesterone, which is needed to sustain a pregnancy. Misoprostol is taken 24 to 48 hours later, causing the uterus to contract and expel pregnancy tissue.
Several FDA-mandated safety requirements remain in effect, including training requirements to certify that prescribers can provide emergency care in the case of excessive bleeding. Pharmacies that dispense the pills also need a certification.