The IUD is a small T-shaped object that is placed into the uterus by a provider. IUDs prevent sperm from reaching the egg or from implanting in the uterus. One type contains copper, and others contain progesterone. IUDs can remain in place for one, five, or ten years, depending on the type.
IUDs are generally recommended for women who have had one or more children. When properly inserted and retained, IUDs are 95–98% effective in preventing pregnancy.