An intrauterine device (IUD) is a type of birth control. It is a small, T-shaped device that a doctor or nurse puts in your uterus by going through your vagina and cervix. These devices are made of flexible plastic and have 2 thin plastic strings that hang out of the cervix. They are very small, a little more than 1 inch (2.5 cm) in width and length.

An IUD is one of the safest, most effective methods for preventing pregnancy. It is a good choice for people, including teens, who do not want to get pregnant for at least 1 year. An IUD can also be used to prevent pregnancy if it is put in within 5 days after you have unprotected sex. This is known as “emergency contraception.”

You can also use IUDs for reasons other than birth control. For example, 1 type of IUD can be used to treat heavy, painful periods.

There are 2 types of IUDs available in the United States. One type releases copper, and the other type releases a progestin-type hormone.

  • Copper-containing IUD – There is only 1 copper-containing IUD. It is called Paragard and can stay in your uterus for 10 years, or longer for some people, to prevent pregnancy. Some people who use it get heavier or longer periods than they had before getting the IUD.
  • Progestin-releasing IUD – There are 4 progestin-releasing IUDs (brand names: Mirena, Kyleena, Skyla, Liletta). Depending on which of these you have, it can stay in your uterus for up to 6, 5, or 3 years. Many people who use progestin-releasing IUDs have lighter, less painful periods than they had before getting the IUD. Some people stop getting a period at all, but this is not harmful and does not need to be treated. Regular periods return when the device is taken out, usually within a month or 2.

Other types of IUDs are also available outside of the United States.

The benefits of using an IUD include:

  • IUDs are very effective. Fewer than 1 in 100 people who use these devices get pregnant during the first year of using them.
  • You do not have to remember to do anything or take any birth control medicines on a regular basis.
  • IUDs have few side effects.
  • IUDs do not contain estrogen, a hormone that some people can’t or don’t want to take.
  • If you decide you want to get pregnant, you can have the IUD taken out.
  • If you use an IUD for several years, it costs less overall than many other types of birth control. That’s because there are no costs after you have it inserted.
  • There is evidence that using an IUD lowers your risk of getting cervical cancer.

The downsides of an IUD include:

  • Unlike condoms, an IUD does not protect you against infections you can catch during sex, called “sexually transmitted infections” or “STIs.” But you and your partner(s) can use condoms to prevent spreading infections.
  • There is a small chance the IUD will come out during your period. If this happens, you will need a new IUD. If you see your IUD in your underwear, on your pad, or in the toilet, call your doctor or nurse.
  • The initial cost is higher than the cost of other methods. But, there are no more costs after it is inserted.
  • Only a doctor or nurse can insert or remove an IUD.

You should not get an IUD if you recently had an infection that spread to your uterus and other nearby organs, called a “pelvic infection.” STDs such as chlamydia and gonorrhea can cause pelvic infections.

Your nurse or doctor can help you choose the right IUD for you.

Paragard might be a good choice if you:

  • Want or need to avoid hormones.
  • Want to avoid big changes in your period, such as not having any periods or bleeding or spotting when you might not expect it.
  • Want birth control for up to 10 years, or possibly more

Mirena, Kyleena, Skyla, or Liletta might be a good choice if you:

  • Have heavy, painful periods. These IUDs can make your periods lighter and less painful.
  • Have pelvic pain from a condition called “endometriosis.” These IUDs might help reduce the pain.
  • Want birth control for up to 6 years, depending on which device you choose

You will likely feel some discomfort and slight cramping after the nurse or doctor puts the IUD into your uterus. People who have never given birth often feel more discomfort than people who have. The cramps generally go away within a day. Over-the-counter pain medicines like ibuprofen (sample brand names: Advil, Motrin) or naproxen (sample brand name: Aleve) can help cramps go away faster.

After the IUD is in place, you should not be able to feel it.

If you have an IUD, see your doctor or nurse right away if:

  • You have bad pain in your lower belly
  • Your period is late or very different from normal
  • You cannot feel the string of the IUD or if the string seems shorter than usual
  • You think your IUD might have moved or fallen out
  • You had sex with someone who has or might have an STD, or you think you have an STD
    ●You have an unexplained fever