Which of the following statement is not correct about oral contraceptive pills?

Options

A. They have to be taken daily for a period of 21 days, starting preferably within the first five days of menstrual cycles.
B. They contain small doses of progestogen- estrogen combination
C. They inhibit ovulation and implantation.
D. Ovum and sperms are prevented from physically meeting with the help of barriers.

Answer

To determine which statement is not correct about oral contraceptive pills, let's analyze each option step by step.

### Step 1: Understand Oral Contraceptive Pills
Oral contraceptive pills (OCPs) are a method of birth control taken by females to prevent pregnancy. They typically contain hormones such as estrogen and progestogen.

### Step 2: Evaluate Each Statement
1. **Statement 1**: "They have to be taken daily for a period of 21 days starting preferably within the first 5 days of menstrual cycles."
- This statement is correct. OCPs are usually taken daily for 21 days, starting within the first 5 days of the menstrual cycle.

2. **Statement 2**: "They contain small doses of progesterone and estrogen combination."
- This statement is also correct. Most oral contraceptive pills contain a combination of estrogen and progestogen (progesterone).

3. **Statement 3**: "They inhibit ovulation and implantation."
- This statement is correct as well. OCPs work by inhibiting ovulation and altering the uterine lining to prevent implantation.

4. **Statement 4**: "Ovum and sperm are prevented from physically meeting with the help of barriers."
- This statement is incorrect. Oral contraceptive pills do not use a barrier method; they work hormonally to prevent ovulation and do not physically block sperm from meeting the ovum.

### Conclusion
The statement that is not correct about oral contraceptive pills is **Statement 4**: "Ovum and sperm are prevented from physically meeting with the help of barriers."

### Final Answer
**Statement 4 is not correct.**

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