Emergency contraceptive pills primarily work by ______.

Correct option is B

Sol. Emergency contraceptive pills (ECPs) primarily work by delaying or inhibiting ovulation, preventing the release of an egg from the ovary. This reduces the likelihood of fertilization by sperm. Most emergency contraceptive pills contain levonorgestrel or ulipristal acetate, which interfere with the hormonal signals responsible for ovulation.
Explanation of each option:
· (a) Initiating menstruation – Incorrect. Emergency contraception does not induce menstruation immediately. It affects ovulation and can alter the timing of the next period.
· (b) Delaying or inhibiting ovulation – Correct answer. The primary mechanism of emergency contraception is to prevent ovulation, ensuring that no egg is available for fertilization.
· (c) Preventing fertilization – Incorrect. While preventing fertilization may be a secondary effect, the main action is stopping ovulation before fertilization can occur.
· (d) Thickening cervical mucus – Incorrect. Regular hormonal contraceptives (e.g., birth control pills) thicken cervical mucus to block sperm entry, but this is not the primary action of emergency contraception.