One woman's IUD fell out without her knowing. Here's why that can happen.

I was 27 years old when I decided on using an intrauterine device, known as an IUD. I had recently given birth to my second son, and I wanted a reliable form of contraception (IUDs are more than 99% effective at preventing pregnancy). I wasn’t overly concerned about side effects, which can include bleeding between periods and cramping.

I chose the copper IUD ParaGard because I wanted something that worked long term — something that I could get and forget about.

After having had my IUD for 10 years, I visited my doctor in 2018 to have it removed. Unfortunately, I hadn’t been consistently getting gynecological checkups and found out that my IUD had fallen out without my knowing.

Expulsion of an IUD refers to an intrauterine device falling out partially or completely. The risk is low, occurring in 2% to 10% of users and varying by IUD type, according to the American College of Obstetrics and Gynecology (ACOG). The organization points out that “some unrecognized expulsions are asymptomatic” and — not surprisingly — “may result in unintended pregnancy.”

I decided last year, at age 40, to get another IUD. This time, I deliberately chose the hormonal IUD Mirena for the benefits of a regulated, lighter period. At my yearly checkup last month, I discovered that it had been partially expelled. The medical term is a “malpositioned IUD,” and when that happens, it no longer provides protection against pregnancy. I didn’t have any symptoms or indications that my IUD had moved. My first thought was, “Not again.”

What increases the risk of IUD expulsion?

There are several risk factors that can lead to an IUD being expelled. It’s more likely to happen to women who have never been pregnant or are younger than 20 years old. Research shows that adolescents ages 14 to 19 have a higher risk of IUD expulsion than older women.

Other reported risk factors for IUD expulsion include heavy or painful periods, strong contractions during menses, incorrect IUD placement, a small uterine cavity and an anteverted (when the uterus tilts forward at your cervix) or retroverted uterus (when the uterus tilts backward at the cervix), said Dr. Kecia Gaither, director of perinatal services at NYC Health + Hospitals/Lincoln in the Bronx, to Yahoo Life.

Dr. Taraneh Shirazian, an NYU Langone gynecologist and founder of Mommy Matters, tells Yahoo Life that “the presence of fibroids or polyps can cause an IUD to expel” as well.

Having an IUD inserted after vaginal delivery or after an abortion may also increase the likelihood of an IUD being expelled. According to a 2018 study of 162 women, 8% who had a copper IUD inserted after vaginal delivery experienced complete IUD expulsion within six months.

For women undergoing a medication abortion during the second trimester, having an IUD inserted early (five to 14 days after) vs. delayed (three to four weeks after) carries a slightly higher risk of IUD expulsion. Experts say, however, that the “benefits of actually getting the IUD outweigh the risks of expulsion” because it offers long-lasting pregnancy protection.

How can you tell if your IUD was expelled?

When an IUD is inserted, there are plastic strings that hang down in the vaginal canal. Regularly checking the strings helps. Signs that an IUD is malpositioned or has been expelled include shorter strings than usual, longer strings than normal, strings that seem uneven, strings that are out of place or missing strings.

Gaither says the signs of IUD expulsion include not being able to “feel the string, heavy bleeding, cramping, discharge, fever, pelvic pain and/or your partner can feel it during sex.”

Shirazian adds that if the IUD is low in the uterine cavity, it will create more pain and cramps.

What should you do if you think your IUD is expelled?

If you suspect your IUD has shifted or fallen out, Gaither advises seeing “your health care provider for an exam. In addition to pelvic sonography, this can confirm if the IUD has been expelled. At this time, options can be discussed as to replacing it versus choosing another contraceptive option.”

Shirazian suggests that “if you are concerned that you have expelled your IUD, please use backup contraception like condoms.”

As for me, I have decided to try again and am having my IUD replaced.

This article has been edited for clarity and length.

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