An Intrauterine Device (IUD) is a T-shaped, plastic device inserted into the uterus by a healthcare professional. There are two types of IUDs available:
- Copper, which can remain in place for 10 to 12 years.
- Progesterone (natural female sex hormone); two types:
- Mirena, lasts five to seven years.
- Other types, replace every year.
IUDs prevent pregnancy by inhibiting fertilization of the egg. Although not entirely known, it is believed that the IUDs affect the way the sperm and egg move and/or affect the lining of the uterus to prevent implantation of the egg.
IUDs are recommended for women in long-term mutually monogamous relationships, such that the risk of getting a sexually transmitted infections (STIs) is low.