Ulipristal Acetate CAS:126784-99-4

Ulipristal acetate is a new type of oral emergency contraceptive and the active chemical ingredient of Ella, a new generation of emergency contraceptives currently on the market in the United States. It can not only be used for up to 120 hours after women have unprotected intercourse, but the effectiveness of emergency contraception will not decrease with the delay of the medication time, and the safety and tolerability are very good. Compared with the most commonly used emergency contraceptive levonorgestrel, ulipristal acetate has a wider clinical applicability and has the potential to prevent more unintended pregnancies.

Ulipristal acetate (UPA) is a selective progesterone receptor modulator. Attributing to its higher efficacy and a similar rate of side effects compared to levonorgestrel emergency contraception, it is now recommended as first line treatment for emergency contraception. Emergency contraception is defined as the use of drug or device after unprotected or under-protected intercourse to prevent an unwanted pregnancy. Ulipristal acetate can be used up to 5 days (120 時間) after unprotected sexual intercourse. As progesterone promotes the growth of uterine fibroids, the blocking characteristic of ulipristal acetate can thereby be used to reduce the size of uterine fibroids. Ulipristal acetate has also shown efficacy with a significant reduction in uterine bleeding caused by uterine fibroids. The treatment of fibroids by ulipristal acetate should begin in the first week of a menstrual period.