The main differences between the levonorgestrel-releasing intrauterine devices (IUDs) for birth control (Kyleena, Liletta, Skyla, and Mirena) are the the duration of effectiveness, the total amount of hormone per device, and the size of the IUD.

The levonorgestrel-releasing intrauterine devices (IUDs) approved by the FDA are considered to be highly effective methods of birth control. They are placed into the uterus by a health care professional and can be used for the maximum approved duration, or removed sooner if required.

The levonorgestrel-releasing IUDs work to prevent pregnancy by thickening the cervical mucus, inhibiting sperm movement, reducing sperm survival, and thinning the lining of the uterus.

The levonorgestrel-releasing IUDs may also work to decrease menstrual flow, and periods may end up being lighter, shorter, or even stop altogether.

Mirena, Skyla, Liletta, and Kyleena can all be used whether or not you have given birth to a child.

The Skyla and Kyleena IUDs are slightly smaller in size than Mirena and Liletta, and may be more suitable for women who have a smaller uterus, such as younger women.