A couple had unprotected intercourse and they are worried pregnancy. The progesterone of choice for emergency contraception is:
Levonorgestrel is more effective for emergency contraception and is associated with fewer side effects than the combination estrogen-progestin regimens. The incidence of pregnancy can be reduced to 2% by the use of emergency contraceptives within 72 hours of unprotected intercourse. Ref: Hall J.E. (2012). Chapter 347. The Female Reproductive System, Infeility, and Contraception. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.
Norethisterone
Medroxyprogesterone acetate
Levonorgestrel
Desogestrel