This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Contraceptives, Subject name: Gynaecology & Obstetrics
Ulipristal acetate is a: 
Select and explain. 
A. GnRH agonist, B. Selective progesterone receptor modulator, C. Androgen antagonist, D. Selective estrogen receptor modulator
B: Selective progesterone receptor modulator
Answer: B: Selective progesterone receptor modulator 
Explanation: Ulipristal Synthetic progesterone hormone receptor modulator Attaches to progesterone receptor and prevents/delays ovulation and suppresses endometrium,prevents implantation. Although not approved for its use in India, it is being tried for its role in medical management of fibroid uterus and as an emergency contraceptive