There are many methods of contraception, and their effectiveness depends on the type of method. Among the most effective contraceptive methods are the Intrauterine Devices (IUDs).
The copper IUD prevents fertilization by creating an inflammatory reaction that damages the sperm and prevents it from meeting the egg.
The hormonal IUD slowly releases the progestin that thickens the cervical mucus, prevents sperm progression, and reduces survival chances. It also alters the lining of the uterus to prevent a fertilized egg from implantation.