Mirena IUD - MacArthur Medical Center


The Mirena Intrauterine Device is a small, plastic T-shaped device that is inserted into the uterus. It uses topical delivery of progestin to the uterine cavity to prevent pregnancy. The Mirena also helps control heavy, painful cycles. It can remain in place for up to five years, but can be removed earlier with a quick return to fertility.  Side effects include altered bleeding patterns for several months, cramping with insertion, IUD expulsion, and a small risk of uterine perforation upon insertion. The Mirena is available to all women, regardless of pregnancy history. You should not get an IUD if you have cervical or uterine cancer, pelvic inflammatory disease, or a distorted uterine cavity.


Kyleena is the newest IUD on the market and differs slightly from some of the other IUDs that have already been widely used. It was created by the makers of the Mirena IUD and features many similarities to it. Here are some quick facts about the Kyleena.

  • The Kyleena is approved for preventing pregnancy for up to 5 years
  • It releases Levornogestrel, a type of progesterone
  • It is the smallest 5-year IUD available
  • It is approved for placement in patients who have never been pregnant
  • It is over 99% effective at preventing pregnancy
  • It is a non-surgical procedure done in the office
  • It has similar side effects to the Mirena including irregular bleeding and spotting, mild cramping during the procedure, and possible expulsion (about 4/100 women)

You might be wondering how to choose between all the different IUDs available on the market. Here is a quick cheat sheet comparing the more commonly used IUDs – The Mirena, Skyla, and Kyleena.



Insertion Tube Size


Mirena (duration 5 years)

52 mg Levornogestrel

4.4 mm

Recommended for women that have had at least 1 child. (>99% effective)

Skyla (duration 3 years)

13.5 mg Levornogestrel

3.8 mm

Approved for insertion in women who have never been pregnant. (>99% effective)

Kyleena (duration 5 years)

19.5 mg Levornogestrel

3.8 mm

Approved for insertion in women who have never been pregnant. (>99% effective)