Ulipristal acetate is a new type of oral emergency contraceptive. Compared with the most commonly used emergency contraceptive levonorgestrel, Ulipristal acetate has a wider clinical applicability and can prevent more unintended pregnancies. potential. Ulipristal acetate is a selective progesterone receptor modulator, which plays an emergency contraceptive effect mainly by inhibiting ovulation. Relevant studies have found that ulipristal acetate is more effective than levonorgestrel in inhibiting vaccinations when administered close to the day of discharge (the pregnancy machine Chemicalbook will be the highest), suggesting that ulipristal acetate may have a more effective effect than levonorgestrel. Strong emergency contraceptive effect.