A Mirena is an intrauterine system (IUS) commonly known as a coil. It is a small plastic ‘T’ shaped device which works by slowly releasing a hormone similar to the natural progesterone that your ovaries produce.
Mirena is a good first choice for women also requiring contraception. It works by thinning the lining of the womb and can therefore be very effective in treating heavy periods. It can also significantly improve period pain.
Generally you would expect to see a reduction in blood loss after 3 months with the maximum benefit 6 months after insertion.