Which of the following is a correct statement w.r.t. contraceptive methods?

Options

A. In conventional vasectomy, usually transabdominal surgery is done , in which fallopian tube is cut and cut eneds are tied
B. Tubectomy inhibitas fertilisation by blocking formation of ova in ovary
C. In coitus interruptus, coupls avoid from coitus from day 10 to 17 of the menstural cycle
D. Surgical intervention blocks gamete transport and thereby prevents conception

Answer

To solve the question regarding the correct statement with respect to contraceptive methods, we will evaluate each of the provided options step by step.

### Step-by-Step Solution:

1. **Evaluate Option A**:
- The statement mentions that in conventional vasectomy, the fallopian tube is cut and the ends are tied.
- **Analysis**: Vasectomy is a surgical procedure for males where the vas deferens (the tube that carries sperm) is cut and tied. It does not involve the fallopian tubes, which are part of the female reproductive system.
- **Conclusion**: This option is incorrect.

2. **Evaluate Option B**:
- The statement claims that tubectomy inhibits fertilization by blocking the formation of ova in the ovary.
- **Analysis**: Tubectomy is a female sterilization procedure where the fallopian tubes are cut and tied, preventing the sperm from reaching the egg. It does not block the formation of ova; rather, it prevents the ova from traveling to the uterus.
- **Conclusion**: This option is also incorrect.

3. **Evaluate Option C**:
- The statement suggests that in coitus interruptus, couples avoid coitus from day 10 to 17 of the menstrual cycle.
- **Analysis**: Coitus interruptus, or withdrawal method, involves the male partner withdrawing before ejaculation. It does not depend on specific days of the menstrual cycle, as it is a method of preventing sperm from entering the vagina during intercourse.
- **Conclusion**: This option is incorrect.

4. **Evaluate Option D**:
- The statement states that surgical intervention blocks gamete transport and thereby prevents conception.
- **Analysis**: Surgical contraceptive methods (like vasectomy and tubectomy) indeed block the transport of gametes (sperm and ova), preventing fertilization and conception.
- **Conclusion**: This option is correct.

### Final Answer:
The correct statement with respect to contraceptive methods is **Option D: Surgical intervention blocks gamete transport and thereby prevent conception.**