IUD Side Effects

Medically Reviewed by Traci C. Johnson, MD on May 01, 2023
3 min read

Nearly 4.5 million women in the U.S. use an intrauterine device (IUD) for birth control. They are very effective at preventing pregnancy -- only one out of every 100 women with an IUD will get pregnant while using the device.

IUDs are also very safe. Some women do have side effects, but they're usually mild. Serious problems from the devices are rare.

Side effects from this birth control method can be different for everyone. The ones you get depend on which type of IUD you have and your medical history.

There's no way to predict how your body will respond to an IUD. If you do have any problems, it's important to let your doctor know about them.

Expect to have period-like cramps for the first few days after your doctor inserts the IUD. Mild cramping is normal. If the pain becomes intense, call your doctor.

Some women feel dizzy after right after their doctor inserts the IUD. A few will faint.

To keep from passing out, lie down until you feel better, then get up very slowly.

Your periods will change after you get the device. Hormonal IUDs (Kyleena, Liletta, Mirena, and Skyla) often make periods lighter and shorter. Sometimes they stop menstruation altogether.

The copper IUD (ParaGard) may make your periods heavier for the first few months.

Some women have spotting or bleeding in between periods. Your cycle may return to normal within 6 months after you get an IUD.

About 1 out of 10 women will get these fluid-filled sacs in their ovaries in the first year after they get an IUD. Cysts usually go away on their own within 3 months.

Most ovarian cysts are harmless and don’t cause any symptoms. But some will cause bloating, swelling, or pain in the lower belly. Pain can become sudden or severe if a cyst ruptures. If you notice these symptoms, talk to your doctor.

Your odds of getting pregnant while you have an IUD are very low -- about 1%. But if it does happen, it could be dangerous. It raises the risk for:

  • Miscarriage
  • Infection
  • Early labor and delivery

If you want to keep the pregnancy, you'll need to have the IUD removed. There are also risks to taking out the IUD while you're pregnant. Ask your doctor about your options.

This is when a fertilized egg implants outside your uterus. The pregnancy can't survive, and it could be dangerous for your health.

Getting pregnant while you have an IUD puts you at a slightly higher risk for an ectopic pregnancy. Each year, only 1 out of 1,000 women with an IUD will have one. It may be a little more likely if you had an ectopic pregnancy, pelvic infection, or surgery on your fallopian tubes in the past.

Let your doctor know right away if you notice belly pain or vaginal bleeding. These could be signs of an ectopic pregnancy.

An IUD slightly raises your odds for an infection of the uterus, fallopian tubes, or ovaries, called pelvic inflammatory disease (PID). Bacteria that cause PID can get into your body when the IUD is inserted.

You’re most likely to get the infection in the first 20 days after you get the IUD. Having more than one sex partner raises your chances of this side effect.

It’s important to treat PID quickly to avoid serious problems. Tell your doctor if you have symptoms like:

  • Belly pain
  • Painful sex
  • Smelly discharge from your vagina
  • Chills
  • Fever
  • Heavy bleeding

Your doctor will prescribe antibiotics to treat PID.

Rarely, the IUD pokes through the wall of the uterus as your doctor inserts it. You will need to have it removed if this happens.

This is when the IUD falls out of the uterus. It happens in about 3% of women. The risk is slightly higher in women who've been pregnant before.

An expulsion causes symptoms like bleeding and pain, but some women don't have any symptoms.

If you think your IUD fell out, don’t try to put it back in yourself. See your doctor to see if they recommend replacing it, or if there’s another form of birth control that would work better for you. Until then, use a condom or other backup birth control method.