A 27‑year‑old woman takes levonorgestrel emergency contraceptive 4 hours after unprotected intercourse. The pill is 95 % effective when taken within 72 hours. If 200 women in a community use the pill under these conditions, how many unintended pregnancies are avoided compared to no emergency contraception?

Step-by-step solution

1. Effective use rate = 95 % → failure rate = 5 %.
2. Number of women = 200.
3. Expected pregnancies without emergency contraception = 200 × 0.05 = 10.
4. These 10 pregnancies are avoided by using the pill.

Concept tested: Emergency contraception effectiveness

Published 22 September 2026 · How this solution was prepared and checked