Mirena is a hormone-releasing IUD that is over 99% effective at preventing pregnancy for as long as you want, for up to 5 years. Mirena is recommended for women who have had a child. Mirena also treats heavy periods in women who choose intrauterine contraception.

Is Mirena Reversible?

Mirena is a small, T-shaped device, also known as an IUD, or intrauterine device placed into the uterus by a trained healthcare provider during an office visit. You should do a monthly self-check to make sure it’s in place—ask your healthcare provider to explain how if you are unsure. Placement of Mirena is nonsurgical and Completely reversible, so you can have it removed at any time and try to become pregnant right away. Everyone is different, and some women may experience discomfort or spotting during and after placement. These symptoms should go away shortly. If they don’t, contact your healthcare provider, as Mirena may not have been properly placed. Within 4 to 6 weeks, you should return for a follow-up visit to make sure that everything is okay.

How Does Mirena Prevent Pregnancy?

Mirena starts working as soon as it is placed in the uterus and may work in several ways:

  • IUD that releases small amounts of a progestin hormone called levonorgestrel into the uterus.
  • It inhibits sperm from reaching/fertilizing an egg.
  • Thickens cervical mucus to prevent sperm from entering the uterus.

Mirena is placed in the uterus, not the vagina, so neither you nor your partner should be able to feel it during sex. If you or your partner do feel pain, talk to your healthcare provider. If you ever have trouble finding the threads or feel more than just the threads, call your healthcare provider right away. And in the meantime, use a non-hormonal form of birth control as a backup.

How Small is Mirena?

The actual height of Mirena is 1.26 inches. But how small is that? About half the height of
a sugar packet or about the same height as a set of stacked dice. Insertion of Mirena only takes a few minutes.


See more children in your future but aren’t ready yet? Or maybe your family is just the right size but you’re not ready for permanent birth control. Either way, Mirena might be right for you. Contact us if you have any questions or to schedule an appointment.

NOTE: If you have a pelvic infection, get infections easily, or have certain cancers, don’t use Mirena. Less than 1% of users get a serious pelvic infection called pelvic inflammatory disease (PID). In addition, Mirena does not protect against HIV or STDs. Mirena lasts for as long as you want, for up to 5 years.

Information provided by Mirena.