Hormonal IUDs

Hormonal IUDs that contain progesterone must be replaced every 5 years. They can be removed at any time if a woman decides she wishes to become pregnant or if she does not want to use it anymore. Hormones are in the arms of the IUD and are released slowly into the uterus.

The Mirena levonorgestrel-releasing intrauterine system (IUS) contains the hormone levonorgestrel (LNg), which is similar to progesterone. The LNg IUS causes cervical mucus to thicken to prevent sperm from entering the cervix and reaching the egg. Only about 1 in 1,000 women who use the LNg IUS experience accidental pregnancy in the first year. The LNg IUS reduces the risk of tubal pregnancies and pelvic inflammatory disease. It also dramatically decreases menstrual blood loss. It is approved to protect women from pregnancy for up to 5 years when used in the United States and 7 years in Europe and Asia.