In emergency which contraceptive methods may be used within 72 hours of coitus.

Answer

**Step-by-Step Solution:**

1. **Understanding Emergency Contraception**: Emergency contraception refers to methods used to prevent pregnancy after unprotected sexual intercourse. It is crucial to act quickly, as these methods are most effective when taken shortly after the event.

2. **Time Frame**: The emergency contraceptive methods must be used within 72 hours (3 days) of unprotected intercourse. This time frame is critical for the effectiveness of the contraception.

3. **Emergency Contraceptive Pills (ECPs)**: The primary method of emergency contraception is the use of Emergency Contraceptive Pills (ECPs). These pills are specifically designed to prevent pregnancy after unprotected sex.

4. **Types of ECPs**:
- **Levonorgestrel**: This is one of the most common types of emergency contraceptive pills. It is effective when taken within 72 hours of unprotected intercourse.
- **Ulipristal Acetate**: Another type of emergency contraceptive that can be taken up to 120 hours (5 days) after unprotected intercourse, but is still effective within the 72-hour window.

5. **Effectiveness**: The effectiveness of ECPs can vary, but studies indicate that they can prevent pregnancy in about 50% to 100% of cases when taken within the recommended time frame.

6. **Conclusion**: In emergencies, the recommended contraceptive method to prevent pregnancy within 72 hours of coitus is the Emergency Contraceptive Pill, specifically Levonorgestrel or Ulipristal Acetate.

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