In periodic abstinence couple avoid coitus from

Answer

**Step-by-Step Solution:**

1. **Understanding Periodic Abstinence**: Periodic abstinence is a natural family planning method where couples avoid sexual intercourse during certain days of the menstrual cycle to prevent pregnancy.

2. **Fertility Awareness**: This method is also known as fertility awareness, which relies on tracking the menstrual cycle to identify fertile days.

3. **Menstrual Cycle Overview**: The average menstrual cycle lasts about 28 days, but it can vary among women. Ovulation typically occurs around 14 days before the next menstrual period begins.

4. **Identifying Ovulation**: To determine when to abstain from coitus, couples need to identify the ovulation period, which is generally around the middle of the menstrual cycle.

5. **Days of Abstinence**: Based on the typical cycle, couples are advised to avoid coitus from day 10 to day 17 of the menstrual cycle. This is when ovulation is expected to occur, and the chances of conception are highest.

6. **Conclusion**: Therefore, in periodic abstinence, couples should avoid coitus from day 10 to day 17 of the menstrual cycle to effectively prevent pregnancy.

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