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

Explanation

To determine which statement about periodic abstinence is incorrect, we can analyze each statement one by one.

### Step-by-Step Solution:

1. **Understanding Periodic Abstinence**:
- Periodic abstinence is a natural contraceptive method where couples avoid sexual intercourse during the fertile period of the menstrual cycle to prevent pregnancy.

2. **Analyzing the Statements**:
- **Statement A**: "The couple should abstain from coitus from day 10 to 17 of the menstrual cycle when ovulation could be expected."
- This statement is **correct**. Couples are advised to abstain during this period as it is when ovulation is likely to occur.

- **Statement B**: "10th to 17th day of the cycle is fertile period when the chances of fertilization are high."
- This statement is **correct**. The days around ovulation are indeed the most fertile, increasing the chances of fertilization.

- **Statement C**: "This prevents the chances of union of male and female gametes."
- This statement is **correct**. By abstaining during the fertile period, the chances of sperm meeting the ovum are reduced.

- **Statement D**: "In this method, the ovum and sperms are prevented from physically meeting with the help of barriers."
- This statement is **incorrect**. Periodic abstinence does not involve any physical barriers; it relies solely on timing to avoid intercourse during the fertile period.

3. **Conclusion**:
- The incorrect statement regarding periodic abstinence is Statement D.

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

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