List three techniques that have been …

The prevention of pregnancy in women (by preventing fertilisation) is called contraception. There are four methods of contraception:

1. Barrier method: In barrier method of contraception, the physical devices such as condoms are used by males and females.
2. Chemical method: In chemical methods of preventing pregnancy, the females use two types of pills – oral pills and vaginal pills.
3. Intra-Uterine Contraceptive Devices – The use of intra-uterine contraceptive devices like Copper-T is very effective in preventing pregnancy.  A Copper-T is placed inside the uterus by a doctor to prevent unwanted pregnancies.
4. Surgical method: These methods are available for males as well as for females. Vasectomy is done in males and tubectomy is done in females.

1. Vasectomy - In males, a small portion of the sperm duct (Vasdeferens) is removed by surgical operation and both the cut ends are ligated properly. This prevents the sperms from coming out.
2.  Tubectomy - In females, a small portion of the oviducts is removed by surgical operation and the cut ends are ligated. This prevents the ovum from entering into the oviducts.