The FDA has approved ella, generically known as ulipristal, to prevent pregnancy up to 5 days following intercourse. That’s 2 days longer than Plan B, the emergency contraceptive currently on the market.

ella was developed by Paris-based HRA Pharma. It has been available in Europe since last year. It will be available in the US later this year, by prescription only. Watson Pharmaceuticals will distribute ella in the US.

The FDA green-lighted ella after reviewing the results of 2 studies. In the first, women who took the drug between 48 and 120 hours after sex experienced a 2.2% pregnancy rate, as compared to a rate of 5.5% among those who hadn’t taken ella. In the second study, women who took the drug within 72 hours after intercourse had a 1.9% pregnancy rate, as compared with an expected rate of 5.6%.

Plan B has been approved for the prevention of pregnancy up to 72 hours following intercourse. It is available without a prescription for women who are at least 17 years old. Younger teens must have a prescription for Plan B.

The FDA’s review of ella rekindled an old debate concerning the effects of emergency contraceptives. Antiabortion advocates argue that they can end pregnancies, not just prevent them.

“The bottom-line concern is that it’s a drug that causes an abortion,” Jeanne Monahan, director of the Family Research Council’s Center for Human Dignity told the Wall Street Journal.

However, the FDA-approved labeling for ella indicates the drug is an emergency contraceptive: it’s use is to prevent pregnancy. The drug works either by inhibiting or delaying ovulation, or by altering the lining of the uterus to hinder implantation of the fertilized egg.

“It’s used to prevent ovulation,” a Watson spokesman told the Journal. “It’s not an abortion drug.”