A Mirena IUD is a small T-shaped intrauterine device (IUD) which is inserted into the cervix and functions primarily as a contraceptive for a period of up to five years. It works by releasing a small amount of progestin into the lining of the uterus. One of the effects of this is to thin the lining of the womb, the endometrium, which in turn results in shorter, lighter periods. For this reason, Mirena IUDs can be prescribed for women who experience heavy periods and in some cases these women may find their periods stop altogether.
Fitting the device is a simple procedure which does not require an anaesthetic. However, the cervix will need to be dilated for the fitting to take place – this process can feel uncomfortable and patients may be prescribed pain killers in advance. The IUD can be removed using forceps. There can also be a few side effects, many of which are comparable to normal menstrual symptoms (such as lower back and abdominal pain, breast tenderness, mood changes) but many patients find the benefits of having a light period outweigh these disadvantages.