A Mirena is a small, T-shaped device that is inserted into the uterus to prevent pregnancy. It is a type of long-acting reversible contraception (LARC). Mirenas are effective for up to 5 years.
It is important to check your Mirena regularly to make sure that it is still in place and working properly. You can check your Mirena by feeling for the strings that hang down from the bottom of the device. The strings should be about 2-3 inches long. If you cannot feel the strings, or if they are shorter or longer than usual, you should see your doctor.