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Intrauterine Contraception (IUD) Fact Sheet

How do I get it?

An IUD can only be inserted by a health care professional. To search for a family planning clinic near you, use the Clinic Locator.

Advantages of an IUD

  • IUDs do not require the consent of the female's partner

  • They are safe and effective in preventing pregnancy

  • The Copper T IUD can also be used as emergency contraception to prevent pregnancy if inserted within five days after unprotected sex

  • IUDs work for many years, often a decade or more

How effective is it?

Of 100 women who use either the ParaGard IUD or Mirena IUS, about one will become pregnant.

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Quick Facts

Effectiveness in Preventing Pregnancy

  • Off 100 women using IUDs, about one will become pregnant


  • Health care provider inserts an IUD into the uterus
  • Is effective for 5-10 years

STI Protection

  • No

Clinic Visit Required

  • Yes, only available through a health care provider

What is an Intrauterine Contraception?

Intrauterine Contraception, or IUC (sometimes referred to as intrauterine device or IUD), is a small T-shaped device made of soft, flexible plastic. Two types are available in the U.S.:

  • ParaGard Intrauterine Copper Contraceptive: Also knows as the Copper T IUD, it is made with copper and plastic and prevents pregnancy by blocking sperm from meeting with and fertilizing an egg
  • Mirena Intrauterine System (IUS): Like the ParaGard, the Mirena IUS works by stopping sperm from meeting with and fertilizing an egg. The Mirena IUS also prevents pregnancy by releasing a small amount of progestin (a hormone found in birth control pills) that keeps the ovaries from releasing an egg. Hormones are chemicals that control how different parts of your body work

How do I use it?

An IUD is placed into the uterus by a health care provider. The ParaGard IUD will prevent pregnancy right away. It may take a week for the Mirena IUS to begin working, so ask if you need to use a back-up method of birth control (like a condom) in the meantime.

Once in place, either device will work well in preventing pregnancy for a very long time. ParaGard IUDs are effective for 10 years or more, while the Mirena IUS will last for at least five years.

Your health care provider will have you return to the office or clinic from time-to-time for check-ups, just to make sure you are doing okay. The first return visit will be about a month or so after the IUD has been placed. It is common for women to have some mild discomfort, cramping, and spotting after the IUD is first inserted. In most cases, though, this will become milder or go away in a few weeks or months. Ask your health care provider about what types of symptoms you should expect and report to him or her.

Your health care provider may also want you to check the IUD on your own between visits to make sure the string from the IUD is in place. They will tell you more about how to do this.

Very rarely, an IUD will slip out of place. This is more common in women who have never had a baby. If the IUD moves or comes out, do not try to put it back yourself! Go to a clinic and have them insert it for you.

Drawbacks of an IUD

  • Requires a clinic visit
  • Provides no protection against sexually transmitted infections (STIs)
  • May cause side effects like cramping and bleeding
  • While not common, a few women will develop pelvic infections with an IUD (most often within three weeks after insertion)
  • Rarely, IUDs will tear a hole in the uterus


Office on Women's Health:

Centers for Disease Control and Prevention

Food and Drug Administration