Dr. Jim Shelton's Pearls: Oral Emergency Contraceptive
Dr. Jim Shelton's Pearls is an occasional series by USAID’s Global Health Science Advisor that answers commonly asked questions about family planning.
Originally posted on September 1, 2010.
Question: I understand the FDA has approved a new emergency contraceptive (EC). Can you please tell me about it?
Answer: Yes, on August 13, 2010 the FDA approved ella (ulipristal acetate) as a new oral emergency contraceptive. Some of its attributes:
- Ella has a larger window of action – up to 120 hours after unprotected sex, compared to 72 hours for LNG. For either, the sooner the EC is taken, the more effective it is.
- It is somewhat more effective than the current standard levonorgestrel (LNG) EC. In comparative clinical studies, women using ella had a 1.8% chance of pregnancy after an episode of unprotected coitus compared to 2.6%. (The expected rate of pregnancy is approximately 5.5% had they not used EC.)
- Ella is a progesterone agonist/antagonist, whereas LNG is a progestin.