Which of the following is an incorrect statement for periodic abstinence?

Options

A. The couple should abstain from coitus from day 10 to 17 of the menstrual cycle when ovulation could be expected
B. 10th to 17th day of the cycle is fertile period, when the chances of fertilisation are high
C. This prevents the chances of union of male and female gametes
D. In this method, the ovum and sperms are prevented from physically meeting with the help of barriers.

Answer

### Step-by-Step Solution:

1. **Understanding Periodic Abstinence**: Periodic abstinence is a method of natural family planning where couples avoid sexual intercourse during the fertile window of a woman's menstrual cycle. This is done to prevent pregnancy.

2. **Identifying the Fertile Window**: The fertile window typically occurs around the time of ovulation, which is when the ovary releases an egg. Ovulation usually occurs around the 14th day of a 28-day menstrual cycle, but this can vary from person to person.

3. **Timing of Abstinence**: Couples practicing periodic abstinence should abstain from sexual intercourse from approximately the 10th to the 17th day of the menstrual cycle, as this is when the chances of conception are highest.

4. **Evaluating the Statements**:
- **Statement 1**: Abstaining from the 10th to the 17th day of the menstrual cycle is correct since this is the fertile period.
- **Statement 2**: It is true that this method prevents the chances of union of male and female gametes, as intercourse is avoided during the fertile window.
- **Statement 3**: The statement that in this method, the ovum and sperm are prevented from meeting with the help of a barrier is incorrect. Periodic abstinence does not involve any physical barriers; it relies solely on timing and awareness of the menstrual cycle.

5. **Conclusion**: The incorrect statement regarding periodic abstinence is the one that mentions the use of a barrier to prevent the meeting of ovum and sperm, as this method is purely based on abstaining during the fertile period without any physical contraceptive barriers.

### Final Answer:
The incorrect statement for periodic abstinence is: "In this method, the ovum and the sperms are prevented from physically meeting with the help of a barrier."

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