An intrauterine device (IUD) is a T-shaped device that an obstetrician-gynecologist (OB-GYN) places in the uterus to prevent pregnancy. However, some can still become pregnant with an IUD.

The IUD is an effective form of contraception. Fewer than 1 in 100 women will become pregnant within 1 year of use.

If a woman with an IUD thinks that they may be pregnant, they should schedule an appointment with a doctor as soon as possible.

They will be able to help determine the best course of action based on where the embryo has implanted, where the IUD is at the time of the pregnancy, and the woman’s wishes.

This article will look at the symptoms of pregnancy with an IUD, as well as the options available.

a woman talking to a doctor about getting pregnant with IUDShare on Pinterest
Women with an IUD should speak to their doctor if they suspect that they are pregnant.

An IUD is an effective method of nonpermanent birth control.

According to the Centers for Disease Control and Prevention (CDC), copper IUDs have a failure rate of 0.8%, while the levonorgestrel intrauterine system has a failure rate of 0.1–0.4%

Getting pregnant with an IUD is unlikely, but it can happen. Pregnancy is possible if a woman has penetrative intercourse within 7 days of implantation.

A woman may also become pregnant with an IUD if it falls out of place. Doctors call this IUD expulsion. When an IUD is in the right place, it will sit at the bottom of the uterus, just past the cervix. The IUD strings extend through the cervix into the vagina.

Although IUD expulsion is typically unlikely, it may be more likely in some women.

According to the American College of Obstetricians and Gynecologists (ACOG), the expulsion rate is 2–10% within 1 year of having the IUD inserted. The ACOG also found that women who breastfeed or who get an IUD shortly after giving birth may also be more likely to have their IUD move.

In some cases, when an IUD moves out of place, it will fall out entirely. A woman may notice that they are not able to find it. In other cases, the IUD may shift positions. If this happens, the woman may not know that their IUD has moved, and they might not experience any symptoms.

If it is noticeable, however, a woman may experience:

  • IUD strings that are shorter than normal or uneven
  • heavy bleeding
  • abnormal cramping
  • unusual vaginal discharge

If a woman notices any of these symptoms, they should see their OB-GYN as soon as possible.

If a woman becomes pregnant while using an IUD, they may notice some typical pregnancy symptoms — particularly if the embryo has implanted in the uterus.

These symptoms may include:

  • nausea
  • fatigue
  • a missed period
  • tender breasts
  • cravings
  • mood changes

Women who become pregnant while using an IUD may also notice that the strings are out of place, missing, or uneven.

Ectopic pregnancy

Women who become pregnant while using an IUD are more likely to have an ectopic pregnancy. Ectopic pregnancies occur when the embryo implants outside of the uterus — usually in the fallopian tubes.

According to the ACOG, a woman with an ectopic pregnancy may notice:

  • lower back pain
  • mild abdominal or pelvic pain
  • abnormal vaginal bleeding
  • mild cramping on one side of the pelvis

As an ectopic pregnancy progresses, a woman may experience some other, more serious symptoms.

These can include:

  • sudden and severe pain in the abdomen or pelvis
  • weakness
  • dizziness or fainting
  • shoulder pain

A woman who has these symptoms should seek immediate medical attention.

According to a review of studies that included 221,800 deliveries from women who became pregnant with an IUD in place, there are several possible complications.

These can include:

Possible complicationRisk if IUD removed before deliveryRisk if IUD retained before deliveryRisk if no IUD before delivery
Preterm delivery14.3%14.1%6.8%
Bacterial infection5%2.7%0.6%
Low birth weight11.3%12.1%6.6%
Pregnancy loss2%1.3%0.5%

As mentioned above, an ectopic pregnancy is also a potential complication. Ectopic pregnancies can result in a ruptured fallopian tube. If this occurs, there may be internal bleeding, which can lead to death.

If a woman suspects that they are pregnant, they should talk to their healthcare provider, who will first confirm the pregnancy.

They will also confirm whether or not the pregnancy is ectopic. If it is, a health professional may need to perform surgery or prescribe medication to terminate the pregnancy.

If they prescribe medication, it may be an injection of methotrexate, which will stop the embryo cells from growing. The body will then absorb the pregnancy within 4–6 weeks.

According to the ACOG, a typical surgical procedure for an ectopic pregnancy is a laparoscopic procedure. During this procedure, a surgeon makes a small incision in the abdomen. They will then remove the pregnancy.

If the pregnancy is not ectopic, management will depend on:

  • gestational age
  • the position of the IUD
  • the visibility of the IUD strings
  • the woman’s wishes

According to the ACOG, if a woman plans to continue with the pregnancy, a doctor should remove the IUD when the strings are visible or when it is in the cervix during the early stages of pregnancy.

Desire to continue the pregnancy

If the woman wishes to continue with the pregnancy, a doctor will perform a pelvic examination. If the IUD strings are visible, the doctor will remove the IUD gently.

If the IUD strings are not visible, a woman may need to undergo an ultrasound to determine its location. The next course of action depends on the location, as below:

  • No IUD found: The woman will need an X-ray to locate the device.
  • IUD within the cervix: The doctor will remove the IUD by pulling the strings.
  • IUD above the cervix: The doctor will talk about the risks and complications of continuing the pregnancy.

Termination

If the woman desires to terminate the pregnancy, the doctor can remove the IUD at the time of surgical termination or before medication termination.

They will also provide information regarding the potential options available:

MedicationSurgery
NoninvasiveInvasive
No sedationSedation, if desired
Unpredictable completion timePredictable completion time
Available during early pregnancyAvailable during early pregnancy
High success rate, approximately 95%High success rate, approximately 99%
Heavy bleedingLight bleeding
Requires follow-up sessions to ensure completion of abortionMay not require follow-up in most cases
Multiple-step processSingle-step process

Medication termination

There are a variety of medications a doctor can prescribe, including:

  • mifepristone
  • misoprostol
  • methotrexate

Side effects may include:

  • heavy bleeding (requiring roughly two maxi pads per hour for 2 hours)
  • nausea
  • vomiting
  • diarrhea
  • headache
  • dizziness
  • changes in body temperature

Surgical termination

This procedure involves an OB-GYN inserting a speculum into the vagina. If the cervix needs to be dilated during the time of the procedure, they will insert and withdraw a series of dilators to increase the size of the opening.

The OB-GYN will insert a plastic tube attached to a suction pump to remove the pregnancy.

Following the procedure, a woman can go home after around an hour. According to the ACOG, however, they should expect cramping for 1–2 days and bleeding that can last for 2 weeks.

It is possible, but not likely, to become pregnant when using an IUD.

The highest chance of pregnancy is during the first few days following the implantation of the IUD. A woman can also get pregnant if the IUD has moved out of place.

If a pregnancy occurs, a doctor will determine where the embryo has implanted to make sure that it is viable. If it is ectopic, they will recommend treatment. If it is viable, they will discuss a woman’s options.