Emergency contraceptives are effective if used within

Options

A. 72 hrs of coitus
B. 72 hrs of ovulation
C. 72 hrs of menstruation
D. 72 hrs of implantation

Answer

**Step-by-Step Solution:**

1. **Understanding Emergency Contraceptives**:
- Emergency contraceptives are birth control pills that can be taken after unprotected intercourse to prevent pregnancy.

2. **Time Frame for Effectiveness**:
- These contraceptives are most effective when taken within a specific time frame after unprotected sex.

3. **Evaluating the Options**:
- **72 hours of coitus**: This refers to the time after unprotected intercourse. This is the correct option because emergency contraceptives are designed to be taken after such events.
- **72 hours of ovulation**: Ovulation is when an egg is released from the ovary. This option is incorrect because the effectiveness of emergency contraceptives is not solely based on ovulation timing.
- **72 hours of menstruation**: Menstruation refers to the shedding of the uterine lining. This option is also incorrect as it does not relate to the timing of taking emergency contraceptives.
- **72 hours of implantation**: Implantation is when a fertilized egg attaches to the uterine lining. This is incorrect because emergency contraceptives are not effective after implantation has occurred.

4. **Conclusion**:
- The correct answer is that emergency contraceptives are effective if used within **72 hours of coitus**.

**Final Answer**: A) 72 hours of coitus.

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