Answer the following:
What is rhythm method?

Explanation

### Step-by-Step Solution:

1. **Definition of Rhythm Method**: The rhythm method, also known as the safe period or calendar method, is a natural family planning technique used to determine fertile and non-fertile days in a woman's menstrual cycle.

2. **Understanding the Menstrual Cycle**: The menstrual cycle typically lasts about 28 days, with ovulation occurring around the middle of the cycle, usually between days 12 to 14.

3. **Ovulation and Ova Viability**: During ovulation, an egg (ova) is released and remains viable for approximately 48 hours. This is the time when a woman is most fertile.

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