Study Comparing Emergency Contraception Effectiveness in Women Who Weight ≥ 80 kg

Open to females ages 18-40

1. Be in good general overall health with no chronic medical conditions that result in periodic exacerbations that require significant medical care.
2. Between 18 and 40 years inclusive at the enrollment visit.
3. Weight ≥ 80 kg.
4. Have regular menstrual cycles that typically occur every 21-35 days when not using hormonal contraception.
5. If subject is postpartum or post-abortal, she must have experienced a menstrual bleed since the pregnancy ended
6. If a subject recently used non-injectable hormonal contraception, one bleeding episode consistent with menses must have occurred since last use;
7. Willing to avoid use of any hormonal or intrauterine contraception until the end of the study;
8. For women with a recent history of Depo Provera use, the most recent injection must have been at least 6 months before study entry, and the subject must have had at least one normal menstrual cycle (2 consecutive menses);
9. Request emergency contraception within 72 hours (3 days) after unprotected coitus, as defined by lack of contraceptive use, condom breakage (including condoms lubricated with spermicide), or other barrier contraceptive method failure;
10. . Have a negative urine pregnancy test at time of screening
11. . Reports all acts of unprotected coitus since her prior menses are within 72 hours prior to enrollment;
12. . Willing to abstain from further acts of unprotected intercourse until the end of the study;
13. . Give voluntary, written informed consent, and agree to observe all study requirements including being available for follow up for at least the next 4 weeks;
14. . Accepts that the risk of pregnancy with oral EC is greater than that following placement of a copper IUD for EC.