Which of the following is not a natural contraceptive method ?

Options

A. Periodic abstinece
B. Coitus interruptus
C. Lactational amenorrhea
D. M.T.P.

Answer

To determine which of the following options is not a natural contraceptive method, we will analyze each option provided:

1. **Periodic Abstinence**: This method involves avoiding sexual intercourse during the fertile window of a woman's menstrual cycle. It is based on fertility awareness and is considered a natural family planning method. Therefore, this is a natural contraceptive method.

2. **Coitus Interruptus**: Also known as the withdrawal method, this involves the male partner pulling out before ejaculation to prevent sperm from entering the vagina. This method does not involve any artificial devices or medications, making it a natural contraceptive method.

3. **Lactational Amenorrhea**: This refers to the natural postpartum infertility that occurs when a woman is exclusively breastfeeding. During this time, ovulation is suppressed, and the chances of conception are significantly reduced. This is also considered a natural contraceptive method.

4. **MTP (Medical Termination of Pregnancy)**: This is a medical procedure used to terminate a pregnancy through the use of medications. It is not a method of contraception but rather a way to end an existing pregnancy. Therefore, it is not a natural contraceptive method.

Based on this analysis, the option that is not a natural contraceptive method is **MTP (Medical Termination of Pregnancy)**.

### Final Answer:
MTP (Medical Termination of Pregnancy)