If the menstrual cycle is of 35 days then what is risk period (cycle start on `1^("st")` day) :-

Options

A. ` 9^(th) to 17^(th)` days
B. ` 11^(th) to 18^(th)` days
C. ` 16^(th) to 24^(th)` days
D. ` 18^(th) to 35^(th)` days

Answer

To determine the risk period in a menstrual cycle of 35 days, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Menstrual Cycle**: The menstrual cycle is typically around 28 days but can vary. In this case, we have a cycle of 35 days.

2. **Identify the Phases of the Menstrual Cycle**: The menstrual cycle consists of two main phases:
- **Follicular Phase**: This is the first phase where follicles in the ovaries mature.
- **Luteal Phase**: This is the second phase that occurs after ovulation.

3. **Determine the Ovulation Day**: Ovulation usually occurs about 14 days before the start of the next menstrual period. For a 35-day cycle, ovulation would occur around day 21 (35 - 14 = 21).

4. **Calculate the Risk Period**: The risk period is typically considered to be the days around ovulation when a woman is most fertile. This period is generally from about 2 days before ovulation to 2 days after ovulation.
- If ovulation occurs on day 21, the risk period would be from day 16 to day 24 (21 - 5 = 16 and 21 + 3 = 24).

5. **Conclusion**: Therefore, for a 35-day menstrual cycle starting on the 1st day, the risk period is from **day 16 to day 24**.

### Final Answer:
The risk period for a 35-day menstrual cycle starting on the 1st day is from **day 16 to day 24**.

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