An adolescent girl requests emergency contraception after unprotected intercourse 48 hours ago. Regarding levonorgestrel-based emergency contraception, the correct statement is:
- A It is effective up to 72 hours after intercourse, with efficacy declining over time ✓
- B It must be taken as two doses 12 hours apart only
- C It acts primarily by inducing endometrial abortion
- D It provides contraceptive protection for the remainder of the cycle
Correct answer: A. It is effective up to 72 hours after intercourse, with efficacy declining over time
Explanation
Levonorgestrel emergency contraception is given as a single 1.5 mg dose (or two 0.75 mg doses 12 hours apart, equally effective) ideally within 72 hours, with efficacy highest the sooner it is taken, roughly halving pregnancy risk overall. Its main action is delaying or inhibiting ovulation; it does not interrupt an established pregnancy. Protection is limited to the current episode, so subsequent intercourse in the same cycle requires further contraception.
Reference: Williams Gynecology, 4th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.