Emergency Contraception: Still Effective After 72 Hours?

The effectiveness of emergency contraception (EC) -- including norgestrel plus ethinyl estradiol (the Yuzpe method) and levonorgestrel alone -- within 72 hours after unprotected coitus has been documented by well-designed clinical trials. These Canadian authors conducted an observational study to determine whether EC would be effective for preventing pregnancy if taken longer than 72 hours after unprotected intercourse. The researchers compared 131 women who received EC within the prescribed time frame of 72 hours and 169 women who received EC between 72 and 120 hours after unprotected intercourse. All patients received 2 regimens of 1 mg of norgestrel and 100 μg of ethinyl estradiol.

The pregnancy rate was 0.8 percent for those in the 72-ho…