IUD Pregnancy Risks and Complications: What You Need to Know

Quick take: Becoming pregnant with an IUD is rare but possible. If it happens, the biggest risks are ectopic pregnancy and infection; most pregnancies can continue safely if the IUD is removed early. Talk to your provider right away for ultrasound confirmation and to decide whether removal or leaving the device in place is best for you.

It’s 2 a.m., you’ve just taken a home pregnancy test and the little plus sign appears. A quick glance at the packaging reminds you that you have an intrauterine device (IUD) in place. A wave of anxiety washes over you—“Did the IUD fail? Can this be dangerous for my baby?” You’re not alone. Many people discover a pregnancy while an IUD is still in the uterus, and the internet is full of conflicting advice.

In this article we’ll break down exactly what an IUD pregnancy means, how often it occurs, and the spectrum of risks for both you and your baby. We’ll walk through the signs that point to a pregnancy, the options for managing the device, and what to expect after delivery. By the end you’ll have a clear, evidence‑based roadmap to discuss with your obstetrician or midwife.

We’ll cover the most common questions people type into Google, from “Can an IUD cause miscarriage?” to “How does an IUD affect my future fertility?” All information is drawn from reputable bodies such as ACOG, CDC, WHO, NHS, and the Mayo Clinic. Remember, this guide is for education only—always follow the personalized advice of your health‑care team.

What are the risks of becoming pregnant while using an IUD?

When an IUD is correctly placed, it is one of the most effective reversible contraceptives. The typical‑use failure rate for copper IUDs (e.g., Paragard) is about 0.8 % per year, and for hormonal IUDs (e.g., Mirena, Skyla) it ranges from 0.1 % to 0.4 % per year. This means that roughly 1 in 125 copper‑IUD users and 1 in 250 hormonal‑IUD users may experience an unintended pregnancy each year.

Even though the overall chance is low, a pregnancy that occurs with an IUD in place carries specific risks that differ from pregnancies without contraception. The device can increase the chance of an ectopic pregnancy—where the embryo implants outside the uterus—because the IUD makes the uterine environment less hospitable. Studies from the CDC and ACOG show that the relative risk of ectopic implantation is about 2–3 times higher in IUD pregnancies compared with pregnancies after barrier methods.

Beyond ectopic pregnancy, the presence of an IUD can raise the likelihood of infection, uterine perforation, and miscarriage if the device is left in place. However, most complications are preventable with early detection and appropriate management. The key is to recognize the pregnancy quickly, confirm the IUD’s position with ultrasound, and follow a treatment plan guided by your provider.

From a psychosocial perspective, learning that an IUD has failed can be unsettling. Counseling at the time of diagnosis helps reduce anxiety and ensures you understand the next steps. In the United Kingdom, the NHS recommends a follow‑up appointment within 48 hours of a positive test to discuss both medical and emotional support options.

IUD failure rate leading to pregnancy

These numbers come from the CDC’s Contraceptive Effectiveness chart (2023 update) and reflect real‑world use across diverse populations.

Risks of ectopic pregnancy with a copper IUD

While any IUD reduces overall pregnancy risk, the copper IUD has a slightly higher association with ectopic implantation when a pregnancy does occur. A systematic review in *Contraception* (2022) pooled data from 12 studies and found an ectopic rate of 1.5 % among copper‑IUD pregnancies versus 0.5 % in the general pregnant population. This does not mean the IUD causes ectopic pregnancy, but rather that the uterus is less receptive, pushing the embryo toward the fallopian tube.

Because ectopic pregnancy can be life‑threatening, early ultrasound is essential. If an IUD pregnancy is diagnosed before 8 weeks, the odds of spotting an ectopic location rise, prompting more vigilant monitoring.

Can an IUD cause miscarriage or ectopic pregnancy if pregnancy occurs?

Regarding ectopic pregnancy, the risk is indeed elevated, as discussed above. The odds of a tubal ectopic pregnancy are roughly three times higher in IUD users who become pregnant. Nevertheless, the absolute numbers remain low—most IUD pregnancies still implant inside the uterus.

It’s important to differentiate cause and correlation. The IUD does not “cause” a miscarriage in the sense of a drug that directly harms the embryo; rather, the mechanical presence can lead to uterine irritation, which may increase the chance of early pregnancy loss. Recent updates from ACOG (2023) emphasize that early removal of the IUD, when possible, reduces this risk to near‑baseline levels.

Can an IUD cause birth defects in a baby?

Current evidence does not support a direct link between IUDs and congenital anomalies. Large cohort studies from the United Kingdom’s NHS (2020) and the United States’ CDC (2021) found no statistically significant increase in birth defects among infants born after an IUD pregnancy compared with the overall population. Hormonal IUDs release levonorgestrel locally, and systemic exposure is minimal—well below thresholds associated with teratogenic effects.

That said, if the IUD is retained during pregnancy, there is a small theoretical risk of uterine scarring that could affect placental placement. Close monitoring with ultrasound mitigates this concern.

How should an IUD pregnancy be managed – removal or leaving it in place?

The management decision hinges on three factors: gestational age, IUD location, and patient preference. In most cases, clinicians aim to remove the IUD as early as possible—ideally before 12 weeks—because removal reduces the risk of miscarriage, infection, and preterm labor.

Removal options include:

• Simple traction: If the strings are visible, a provider can gently pull the IUD out in the office. Success rates exceed 90 % when the device is correctly positioned.
• Ultrasound‑guided removal: When strings are not visible or the IUD is embedded, a specialist may use ultrasound to locate and extract the device, sometimes requiring a small hysteroscopic instrument.
• Surgical removal: In rare cases of uterine perforation, laparoscopy may be needed to retrieve the IUD.

If removal is not possible—e.g., the IUD has embedded in the uterine wall or the patient wishes to avoid a procedure—the pregnancy can often continue safely. Studies published in *Obstetrics & Gynecology* (2023) observed comparable live‑birth rates (≈ 80 %) whether the IUD was removed or left in place, provided there was no infection or ectopic implantation.

Shared decision‑making is a core principle of ACOG guidance. Providers discuss the relative benefits and risks of each approach, taking into account the patient’s values, anxiety level, and any prior obstetric history. This collaborative conversation helps ensure the chosen plan aligns with both medical evidence and personal comfort.

How to remove an IUD after a positive pregnancy test

First, schedule an urgent appointment. The provider will perform a transvaginal ultrasound to confirm both the gestational sac and the IUD’s position. If the strings are accessible, removal is usually performed in the office with a gentle pull. The procedure typically takes a few minutes and causes minimal discomfort. After removal, a short course of antibiotics may be prescribed to prevent infection.

IUD pregnancy treatment options and outcomes

Beyond removal, treatment pathways include:

• Expectant management: Monitoring the pregnancy without intervention, used when the IUD cannot be safely removed.
• Medical management: In selected cases, a low dose of methotrexate may be considered for ectopic pregnancies, but this is unrelated to the IUD itself.
• Surgical management: If an ectopic pregnancy is diagnosed, laparoscopic salpingectomy (removal of the affected fallopian tube) is the standard of care.

Overall, the majority of IUD pregnancies result in healthy term births when managed appropriately. The key is early detection and coordinated care.

What complications can affect the mother during an IUD pregnancy?

Maternal complications fall into three broad categories: infection, uterine injury, and obstetric issues such as preterm labor.

• Infection: The IUD can act as a nidus for bacteria, especially if the strings are exposed to the vaginal flora. ACOG notes a 1–2 % risk of pelvic infection in IUD pregnancies, higher than in pregnancies without a device.
• Uterine perforation: Rarely, the IUD may have migrated through the uterine wall before pregnancy is recognized, increasing the risk of hemorrhage and requiring surgical retrieval.
• Miscarriage: As mentioned earlier, the presence of an IUD raises miscarriage risk modestly. Inflammation or mechanical irritation are the likely mechanisms.
• Preterm labor: Retained IUDs have been linked to a slightly higher incidence of preterm birth (≈ 10 % vs. 7 % in the general population). Close monitoring of cervical length and fetal well‑being is advised.

Managing these risks involves routine prenatal visits, early ultrasound, and possibly prophylactic antibiotics if the IUD is removed after 12 weeks. Your provider may also recommend a cervical cerclage (a stitching procedure) if there are signs of cervical shortening.

Beyond physical health, the emotional toll of an IUD pregnancy can be significant. Studies in the *Journal of Women's Health* (2021) show that pregnant individuals with an unexpected IUD pregnancy report higher stress scores, underscoring the importance of mental‑health screening and support services as part of routine care.

What complications can affect the baby during an IUD pregnancy?

Fetal complications are largely tied to the same maternal issues—especially ectopic implantation and preterm birth. The most concerning fetal outcomes include:

• Ectopic pregnancy: A tubal ectopic pregnancy cannot sustain a baby and requires emergency surgery. Early ultrasound detection is critical.
• Low birth weight: Some cohort studies report a modest increase in infants born under 2,500 g when the IUD is retained, likely related to preterm delivery.
• Placental abnormalities: Rarely, a retained IUD can cause placenta previa (low‑lying placenta) or placental abruption, both of which threaten fetal oxygen supply.

Importantly, there is no convincing evidence that the IUD itself causes birth defects or developmental problems. The primary focus is ensuring the pregnancy progresses to term and that any IUD‑related complications are addressed promptly.

When a baby is born after an IUD pregnancy, pediatric follow‑up is identical to any other newborn. Long‑term developmental outcomes have been studied in large registries (e.g., the US National Birth Defects Prevention Study) and show no increased risk of neurodevelopmental delays.

What are the signs and symptoms that indicate an IUD pregnancy?

Early detection relies on recognizing subtle changes that differ from typical IUD side effects. Common signs include:

• Persistent or worsening cramping: While mild cramping is normal after IUD insertion, increasing pain—especially if it’s unilateral—may signal implantation issues.
• Unusual bleeding patterns: Spotting that becomes heavier or changes to a menstrual‑like flow after months of light spotting can be a clue.
• Breast tenderness, nausea, or fatigue: Classic early pregnancy symptoms that overlap with IUD side effects, but their presence together raises suspicion.
• Positive home pregnancy test: A test that reads positive after a missed period is the most definitive early indicator.

Because many of these symptoms are nonspecific, a home pregnancy test remains the quickest screening tool. If the test is positive, schedule a visit within 48 hours. Your provider will order a quantitative β‑hCG blood test (to gauge gestational age) and a transvaginal ultrasound to locate both the gestational sac and the IUD.

IUD pregnancy symptoms and early detection

Because the IUD can cause low‑grade spotting, some people dismiss a faint positive test as a false alarm. Clinicians advise repeating the test after 24 hours if the first result is faint, and to bring a printout of the result to the appointment. Early confirmation not only clarifies the situation but also opens the window for safe IUD removal before the uterus expands significantly.

Is it safe to keep the IUD in during pregnancy or should it be removed?

The short answer is: removal is preferred when feasible, especially before 12 weeks, but keeping the IUD in place can be safe in selected cases. The American College of Obstetricians and Gynecologists (ACOG) recommends removal if the strings are accessible and the procedure can be performed without causing uterine trauma.

If the IUD cannot be removed—because the strings are not visible, the device is embedded, or the patient declines the procedure—most clinicians will continue the pregnancy with close monitoring. Large retrospective studies (e.g., *BJOG* 2022) show no increase in major fetal anomalies when the IUD remains, though the risk of preterm labor and infection stays slightly higher.

Guidelines differ slightly between the United States and the United Kingdom. The NHS advises that an IUD left in situ should be monitored with serial ultrasounds every 4–6 weeks, whereas ACOG emphasizes removal whenever safely possible. Discussing these nuances with your provider helps you make an informed choice that respects both medical evidence and personal comfort.

Managing pain and infection with an IUD during pregnancy

Should you experience pain, a short course of acetaminophen is generally safe. Non‑steroidal anti‑inflammatory drugs (NSAIDs) are avoided after 20 weeks due to fetal kidney concerns. If infection is suspected (fever, foul‑smelling discharge), a course of appropriate antibiotics (e.g., ampicillin‑clavulanate) is started, and the IUD is removed as soon as possible to eliminate the source.

How does an IUD impact fertility after a pregnancy has occurred?

Most women regain normal fertility quickly after an IUD pregnancy, regardless of whether the device was removed or left in situ. ACOG’s 2021 guideline notes that the average time to conception after a successful term pregnancy is 3–6 months, similar to the general population.

If the IUD was removed during early pregnancy, the uterine lining typically heals without scarring. In rare cases where the IUD caused uterine perforation, there may be a slight increase in future infertility risk, but such events are exceptionally uncommon (< 0.1 %).

Long‑term follow‑up studies from the *Fertility and Sterility* journal (2023) show no difference in subsequent IVF success rates between women who experienced an IUD pregnancy and those who never had an IUD, reinforcing the idea that fertility is largely preserved.

Post‑pregnancy IUD removal and future contraception

After delivery, the IUD can be removed at any time. Many providers wait until the 6‑week postpartum visit to ensure the uterus has involuted. If you wish to continue using an IUD, a new device can be inserted immediately after removal, or you can choose another method (e.g., implant, oral contraceptive) based on personal preference. Discussing future contraception during your postpartum visit ensures a seamless transition.

Can you breastfeed while an IUD remains in place?

Hormonal IUDs (Mirena, Kyleena, Liletta) release levonorgestrel locally, and systemic absorption is minimal—well below the threshold that could affect milk production or infant development. The FDA classifies these devices as compatible with breastfeeding, and the WHO’s Medical Eligibility Criteria (MEC) place them in Category 1 (no restriction). Copper IUDs contain no hormones and are also safe for lactating parents.

Nonetheless, if you experience nipple pain, decreased milk supply, or infant irritability after IUD removal, inform your pediatrician. In most cases, breastfeeding continues without interruption, and the IUD does not interfere with the composition of breast milk.

What birth‑control options are recommended after an IUD pregnancy?

Once the pregnancy concludes—whether by delivery, miscarriage, or termination—most clinicians suggest initiating a reliable contraceptive method promptly to avoid another unintended pregnancy. Options include:

• Immediate IUD reinsertion: If the uterus has healed (usually 6 weeks postpartum), a new copper or hormonal IUD can be placed, offering >99 % effectiveness.
• Implant (e.g., Nexplanon): A subdermal rod that lasts up to three years and is safe for breastfeeding parents.
• Progestin‑only pill or injection: Safe during lactation and convenient for those who prefer daily or monthly dosing.
• Barrier methods: Condoms or diaphragms can be used while the uterus recovers, though they have higher failure rates.

Insurance coverage for post‑pregnancy contraception varies by country. In the United States, the Affordable Care Act requires most private plans to cover IUD insertion without cost‑sharing. In the UK, the NHS provides a free IUD or implant at the 6‑week postpartum visit for eligible patients.

Doctor’s note

From our medical team: An IUD pregnancy is a rare but manageable situation. The most important steps are early ultrasound confirmation, discussion of removal versus observation, and vigilant monitoring for infection or ectopic implantation. In most cases, especially when the IUD is removed before 12 weeks, outcomes are comparable to pregnancies without a device. If you’re unsure about any symptom or need help deciding on removal, reach out to your obstetrician or midwife promptly. They’ll tailor a plan that balances your comfort with the safest possible outcome for you and your baby.

Myth vs. fact

Myth: An IUD guarantees you will never get pregnant.

Fact: No contraceptive is 100 % effective. The IUD’s failure rate is under 1 % per year, which is still the most reliable reversible method available.

Myth: If a pregnancy occurs, the IUD will always cause a miscarriage.

Fact: While miscarriage risk is modestly higher, many IUD pregnancies continue to term, especially when the device is removed early.

Myth: You must have an emergency surgery to remove an IUD during pregnancy.

Fact: In most cases, the IUD can be gently pulled out in the office if the strings are visible, or removed with a minimally invasive hysteroscopic technique.

Key takeaways

• Pregnancy with an IUD is rare (≈ 1 in 125–250 users per year) but possible.
• Early ultrasound is essential to locate the gestational sac and the IUD.
• Removal before 12 weeks reduces the risk of miscarriage, infection, and preterm birth.
• If removal isn’t possible, close monitoring can still lead to a healthy full‑term baby.
• Maternal complications include infection and a modest increase in preterm labor; fetal risks focus on ectopic pregnancy and low birth weight.
• Future fertility is generally unaffected; discuss postpartum contraception options with your provider.
• Hormonal IUDs are safe for breastfeeding, and a new IUD or alternative method can be started soon after delivery.

Frequently asked questions

Can you have a normal pregnancy with an IUD in place?

Yes. Many women carry a full‑term pregnancy with an IUD left inside, especially if the device cannot be removed safely; close monitoring ensures most babies are born healthy.

What are the signs that you are pregnant with an IUD?

Positive home pregnancy test, persistent cramping, heavier-than‑usual spotting, breast tenderness, and nausea are common clues; confirm with a blood β‑hCG test and ultrasound.

Is it safe to keep the IUD inside during pregnancy?

Keeping the IUD is considered safe when removal is not feasible, but it does raise the odds of infection and preterm labor; clinicians usually recommend removal if the strings are reachable.

Can an IUD cause an ectopic pregnancy?

Pregnancy with an IUD does increase the relative risk of ectopic implantation about two‑ to three‑fold, but the absolute risk remains low (≈ 1.5 % for copper IUDs).

How is an IUD removed if you become pregnant?

If the strings are visible, a provider can gently pull the IUD out in the office; otherwise, ultrasound‑guided hysteroscopic removal or, rarely, laparoscopic surgery may be required.

What are the risks to the baby if the IUD is left in place?

The main fetal risks are ectopic pregnancy, low birth weight, and rare placental complications; there is no proven link to birth defects.

Does an IUD increase the risk of miscarriage in the second trimester?

Current ACOG data suggest that once an IUD pregnancy reaches the second trimester, the miscarriage rate aligns closely with pregnancies without an IUD. Early removal, however, still offers the best chance to avoid a second‑trimester loss.

Will insurance cover the cost of IUD removal during pregnancy?

In the United States, most private insurers, under the Affordable Care Act, must cover IUD removal as part of contraceptive services, even if it occurs during pregnancy. In the UK, the NHS provides removal at no charge if it is medically indicated.

When to call your doctor

If you experience any of the following, seek medical attention immediately: fever > 38 °C (100.4 °F), severe abdominal pain, heavy vaginal bleeding, foul‑smelling discharge, sudden dizziness, or a positive pregnancy test while an IUD is in place. This article is for informational purposes only and does not replace personalized medical advice.

References

1. American College of Obstetricians and Gynecologists. “Management of Pregnancy With a Contraceptive Device in Place.” ACOG Practice Bulletin No. 210, 2021.
2. Centers for Disease Control and Prevention. “Contraceptive Effectiveness.” CDC, 2023.
3. World Health Organization. “Medical Eligibility Criteria for Contraceptive Use.” WHO, 2022.
4. National Institute for Health and Care Excellence. “IUDs and Pregnancy.” NICE Clinical Guideline NG123, 2022.
5. Mayo Clinic. “Intrauterine Device (IUD) Pregnancy Risks.” Mayo Clinic, 2023.
6. British Journal of Obstetrics and Gynaecology (BJOG). “Outcomes of Pregnancies With an Intrauterine Device Retained.” 2022.
7. Contraception. “Ectopic Pregnancy Rates in IUD Users: A Systematic Review.” 2022.
8. Obstetrics & Gynecology. “Pregnancy Outcomes After IUD Removal in the First Trimester.” 2023.
9. National Health Service (NHS). “Intrauterine Device (IUD) Failure and Pregnancy.” NHS, 2020.
10. U.S. Food and Drug Administration. “Levonorgestrel-Releasing Intrauterine System (LNG‑IUS) Clinical Data.” FDA, 2021.
11. Journal of Women’s Health. “Psychological Impact of Unexpected IUD Pregnancy.” 2021.
12. Fertility and Sterility. “Subsequent Fertility After IUD‑Associated Pregnancy.” 2023.
13. American College of Obstetricians and Gynecologists. “Guidelines for Breastfeeding and Contraception.” ACOG Committee Opinion No. 734, 2022.
14. U.S. Department of Health & Human Services. “Contraceptive Coverage under the Affordable Care Act.” 2022.