The PREVEN ; Emergency Contraceptive Kit is intended to prevent
pregnancy after known or suspected contraceptive failure or
unprotected intercourse. Emergency contraceptive pills (like all
oral contraceptive pills) do not protect against infection with HIV
(the virus that causes AIDS) and other sexually transmitted
The PREVEN ; Emergency Contraceptive Kit consists of a patient information book, a urine pregnancy test and four (4) contraceptive pills (ECPs).
If one hundred women used ECPs correctly in one month, about two women would become pregnant after a single act of intercourse. If no contraception is used about eight women would become pregnant after a single act of intercourse. Therefore, the use of ECPs results in a 75% reduction in the number of pregnancies to be expected if no ECps were used after unprotected intercourse. Notably some clinical trials have shown that efficacy was greatest when ECps were taken within 24 hours of unprotected intercourse, decreasing somewhat during each subsequent 24-hour period.
The most common side effects are: