Risks of Becoming Pregnant With an IUD

Intrauterine devices (IUDs)—small, flexible devices shaped like the letter T that are inserted into a woman's uterus by a doctor—are one of the most effective reversible methods of birth control available. That said, around one of 100 women with an IUD get pregnant each year, with the highest risk occurring within the first year following the insertion.

While it is rare to become pregnant with an IUD, it does occur, and it is important to learn about the risks and complications associated with an IUD pregnancy.

What to Do

According to a 2018 review in the Canadian Medical Association Journal, unintended pregnancy rates in the first year after IUD insertion are 0.8% for the non-hormonal IUD and 0.2% for the hormonal IUDs.

If you suspect that you have conceived while using an IUD, there are three steps you should immediately take:

1. Take a pregnancy test. You can take a home pregnancy test or schedule a blood pregnancy test with your doctor.
2. See your doctor. Getting pregnant while using an IUD increases the risk of an ectopic pregnancy (in which the egg implants outside of the uterus). If pregnancy has occurred, it is important to see your obstetrician as soon as possible.
3. Have the IUD removed. Should you have a viable, non-ectopic pregnancy while your IUD is in place, your doctor will likely recommend the removal of your IUD. Never remove an IUD on your own as it can lead to pregnancy complications.

Potential Risks

There are several reasons why doctors will recommend IUD removal for the health of yourself and your baby. This includes the increased risk of miscarriage, infection, and preterm delivery. Removing the IUD significantly reduces the risk of complications but does not eliminate them.

Miscarriage

Women who become pregnant with an IUD are more likely to miscarry than women who do not. Studies have shown that women who decide to leave the IUD in after conception have a 40% to 50% greater risk of a miscarriage than women who have them removed.

Removing the IUD early in pregnancy appears to reduce the risk of miscarriage. However, the overall risk of miscarriage is still higher than a woman who gets pregnant without an IUD.

Preterm Birth

In addition to miscarriage, leaving an IUD in place during your pregnancy increases the likelihood of preterm birth. Some studies suggest that doing so increases the risk of preterm birth by up to five-fold compared to women who have them removed.

Infection

There is always the possibility that an infection called chorioamnionitis may occur in women who have IUDs. Chorioamnionitis—an infection of the placental membranes as well as the amniotic fluid that surrounds the baby—is serious and potentially life-threatening.

As with preterm birth and miscarriage, having your IUD taken out decreases the risk of chorioamnionitis, but not to zero.

Placental Abruption

There may also be a link between becoming pregnant with an IUD and developing placental abruption, a complication in which the placenta separates from the uterus either before or during delivery. Such an event can lead to significant blood loss, pregnancy loss, and, in some cases, death to the mother.

Hormone Exposure

Of the five IDUs approved for use in the United States, one is non-hormonal (Paragard) and the other four are hormonal:

• Kyleena
• Liletta
• Mirena
• Skyla

If you become pregnant with a hormonal IUD, the device will continue to deliver the hormone progestin to the uterus. The effect of such exposure on the baby has not been established, although animal studies have suggested that it may increase the risk of birth defects.

 A Word From Verywell

Learning about the possible risks and complications associated with an IUD can be daunting and sway you from using the device. But, as with any form of birth control, there are benefits as well as consequences of use.

If you do become pregnant while using an IUD, don't assume the worse; many such pregnancies turn out perfectly fine. Instead, let your doctor know the moment pregnancy occurs. If you decide to continue the pregnancy, keep your recommended perinatal appointments to monitor for any possible concerns.