In Emergency contraception which progesteron is used –
**Core Concept**
Emergency contraception refers to the use of medications to prevent pregnancy after unprotected sex or contraceptive failure. Progesterone medications are used to interfere with ovulation, fertilization, or implantation in the uterus.
**Why the Correct Answer is Right**
Ulipristal acetate is a selective progesterone receptor modulator (SPRM) that works by blocking the action of progesterone in the body, thus preventing ovulation and fertilization. It is used for emergency contraception in a single 30mg dose, taken within 120 hours of unprotected sex. Ulipristal acetate is more effective than levonorgestrel and has a longer window of use.
**Why Each Wrong Option is Incorrect**
**Option A:** Not a commonly used progesterone for emergency contraception.
**Option B:** Ethinyl estradiol is a form of estrogen, not a progesterone.
**Option C:** Not a widely used or recommended progesterone for emergency contraception.
**Clinical Pearl / High-Yield Fact**
Ulipristal acetate is a newer option for emergency contraception and is more effective than levonorgestrel, but it is also more expensive. It is essential to note that emergency contraception is most effective when used within 24 hours of unprotected sex.
**Correct Answer: C. Ulipristal acetate.**