Intrauterine devices (IUD) (The Basics)

What is an intrauterine device? — An intrauterine device (IUD) is a type of birth control. It is a small, T-shaped device that a doctor or nurse puts through your vagina and cervix into your uterus. These devices are made of flexible plastic and have 2 plastic strings similar to fishing line that hang out of the cervix.

An IUD is 1 of the safest, most effective methods for preventing pregnancy. It is a good choice for women who do not want to get pregnant for at least 1 year.

Some women use IUDs for reasons other than birth control. For example, 1 type of IUD can be used to treat heavy, painful periods. The other type can be used to prevent pregnancy if it is put in within 5 days after a woman has sex without birth control. This is known as “emergency contraception.”

What are the different types of IUDs? — There are 2 types of IUDs. One type releases copper; the other releases the hormone progestin.

  • Copper–releasing IUD – There is only 1 copper-releasing IUD. It is called Paragard (picture 1) and can stay in your uterus for up to 10 years to prevent pregnancy. Some women who use it get heavier or longer periods than they had before getting the IUD. Paragard also can be used for emergency contraception.
  • Progestin-releasing IUD – There are 2 progestin-releasing IUDs, called Mirena and Skyla. Mirena (picture 2) can stay in your uterus for up to 5 years to prevent pregnancy. Skyla can stay in place for up to 3 years. Many women who use progestin-releasing IUDs have lighter, less painful periods than they had before getting the IUD. Some women 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.

What are the benefits of using an IUD? — The benefits of using an IUD include:

  • IUDs are very effective. Fewer than 1 in 100 women 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 women can’t or don’t want to take.
  • If you decide you want to get pregnant, you can have the IUD taken out.

What are the downsides of an IUD? — The downsides of an IUD include:

  • Unlike condoms, an IUD does not protect you against infections you can catch during sex, called “sexually transmitted diseases” or “STDs.” But your partner can use a condom to protect against transmitting infection.
  • There is a small chance the IUD will come out during your period. If this happens, you will need a new IUD.
  • You should check your IUD once a month, after your period. To do this, use your finger to check that you can feel the string from the IUD coming out of your cervix. If you cannot feel the string, you should use another type of birth control (such as condoms) until you can see a doctor or nurse to check if your IUD is still in the right place.
  • The initial cost is higher than the cost of other methods. But there is no cost for 3 to 10 years after the initial cost.
  • 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.

Which type of IUD is best for me? — 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. This includes women who have had blood clots in their legs.
  • Want to avoid big changes in your period, such not having any periods or bleeding or spotting when you might not expect it.
  • Want birth control for up to 10 years.

Mirena or Skyla might be a good choice if you:

  • Have heavy, painful periods. Mirena and Skyla can make your periods lighter and less painful.
  • Want birth control for up to 5 years.

Does it hurt to have an IUD put in? — You will likely feel some discomfort and slight cramping after the nurse or doctor puts the IUD into your uterus. Women who have not had a baby often feel more discomfort than women who have had a baby.

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

Should I see a doctor or nurse? — 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 had sex with someone who has or might have an STD, or you think you have an STD
  • You have an unexplained fever

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