The most commonly used IUD(intra uterine device)  is the copper IUD (such as Paragard). Copper wire is wound around the stem of the T-shaped IUD. The copper IUD can stay in place for at least 10 years and is a highly effective form of contraception. Copper is toxic to sperm. It makes the uterus and fallopian tubes produce fluid that kills sperm. This fluid contains white blood cells  copper ions, enzymes.Risks of using an intrauterine device (IUD) include menstrual irregularities,back pain (most common) perforation and expulsion.

it prevents pregnancy its insertion is simple but only thing is your wife should keep on checking the threads so that you should see a doctor to see if it is in place or lost. Your wife should not have any sexually transmitted diseases earlier she should not be pregnant now she should not have any abnormal pregnancy anytime before. infact it is most preferred contraceptive. see your doctor for her advise of the wound of the ceaserean. if it is good and well healed your doctor may insert the Cu -T. the life of Cu T is variable and it works for more than 5 to 8 yrs sometime