The problems of the IUD for the vagina: what is the truth?

Intrauterine devices (IUDs) are among the most effective forms of reversible contraception available today. Despite a troubled history with early models that caused serious harm, modern IUDs are considered safe for most people and are used by millions worldwide. However, like any medical device, IUDs can be associated with adverse effects and complications — some common and benign, others rare but potentially serious. This article provides a comprehensive, evidence-based review of the possible problems associated with IUDs, how they occur, how frequently they happen, and when to seek medical care. Sources for clinical recommendations include the American College of Obstetricians and Gynecologists (ACOG), the National Institutes of Health (NIH/NICHD), the Mayo Clinic, and the Cleveland Clinic.

Overview: what is an IUD?

An intrauterine device (IUD) is a small, typically T-shaped contraceptive device placed inside the uterine cavity through the cervix. There are two main categories:

  • Copper IUDs (non-hormonal), which release copper ions that are toxic to sperm and prevent fertilization.
  • Levonorgestrel-releasing IUDs (hormonal), which release a progestin locally in the uterus to thicken cervical mucus, thin the endometrial lining, and reduce sperm mobility; some users also experience reduced or absent menstrual bleeding.

IUDs provide long-acting reversible contraception (LARC) with durations ranging from about 3 to 10 years depending on the specific product. They are highly effective: failure rates are below 1% per year for properly placed devices (ACOG; Mayo Clinic) [1,2].

Brief historical context

Early IUD models in the 1970s, most notably the Dalkon Shield, were associated with high rates of infection, uterine injury, and other severe complications. Those outcomes were due to design defects and manufacturing issues that have since been addressed. Modern IUDs undergo rigorous clinical testing and have a substantially improved safety profile. Nevertheless, the historical problems continue to influence public perception and underscore the importance of device design, provider training, and appropriate patient selection (ACOG; NIH) [1,3].

How IUDs are placed and how they work

Placement is performed by a trained clinician in an outpatient setting. The procedure involves sterile technique, a speculum exam, cleansing, measurement of the uterine cavity (optional), and placement of the device through the cervical canal into the uterine fundus. Most modern insertions are completed within a few minutes. Pain and cramping are common during insertion; local or oral analgesia may be offered (Mayo Clinic; Cleveland Clinic) [2,4].

Mechanisms of action:

  • Copper IUD: primarily spermicidal effect in the uterine and tubal environment.
  • Levonorgestrel IUD: thickening of cervical mucus to block sperm, suppression of endometrial proliferation, and alteration of tubal motility; in some users, ovulation may be suppressed intermittently.

Common, expected side effects

These are typically mild to moderate and often improve over the first few months after insertion.

  • Cramping and pelvic pain: Common during insertion and for several hours to days afterward; mild intermittent cramping may persist for weeks.
  • Changes in menstrual bleeding:
  • Copper IUD: may increase menstrual bleeding and dysmenorrhea (heavier, longer periods and worsening cramps), particularly initially [2].
  • Levonorgestrel IUD: often reduces menstrual bleeding; many users experience lighter periods or amenorrhea after several months [2].
  • Spotting between periods: Occurs more frequently in the early months with levonorgestrel IUDs.
  • Vaginal discharge: Minor changes in discharge can occur; any malodorous or purulent discharge should prompt evaluation for infection.

These expected effects are discussed in clinical guidance documents and patient information resources (ACOG; Mayo Clinic) [1,2].

Less common but important complications

While serious complications are uncommon, clinicians and users should be aware of them.

Expulsion

Partial or complete expulsion (device falling out) occurs in approximately 2–10% of users, with highest rates in the first few months after insertion. Risk factors include younger age, heavy menstrual bleeding, high parity or recent delivery, and improper placement. Expulsion may be asymptomatic or present with cramping, bleeding, or a change in or loss of the IUD strings felt at the cervix. If expulsion is suspected, pregnancy or removal is possible; users should seek evaluation promptly (ACOG; Cleveland Clinic) [1,4].

Uterine perforation

Perforation of the uterine wall during insertion is rare, estimated at about 1 per 1,000 insertions or less. Perforation may be complete (device exits the uterus into the abdominal cavity) or partial. Risk is higher during insertion in the immediate postpartum or lactation period and when uterine anatomy is distorted. Perforation can cause pain, bleeding, and rarely injury to adjacent organs; ultrasound or radiography is used to locate a missing IUD, and laparoscopic removal is sometimes required (ACOG; Mayo Clinic) [1,2].

Infection and pelvic inflammatory disease (PID)

The overall risk of pelvic infection with IUD use is low. Most PID cases occur in the first 20 days after insertion and are usually related to preexisting sexually transmitted infections (STIs) such as chlamydia or gonorrhea rather than the device itself. For this reason, screening for STIs per guidelines and treating active infections before insertion is a standard precaution. IUD insertion is contraindicated in the presence of untreated pelvic infection. Long-term PID risk with IUD use is not increased compared with those not using an IUD after the initial insertion period (ACOG; NIH) [1,3].

Pregnancy with an IUD in place and ectopic pregnancy risk

Pregnancy can rarely occur with an IUD in place. If this happens, prompt evaluation is required because there is an increased relative proportion of ectopic (tubal) pregnancy among pregnancies that occur with an IUD — not because the device increases the absolute risk of ectopic pregnancy, which remains low due to the overall protection against pregnancy. If an intrauterine pregnancy occurs with an IUD in place, management depends on device location, gestational age, and patient preference; removal of the IUD can reduce the risk of miscarriage and preterm delivery but carries its own risks and considerations (ACOG; Mayo Clinic) [1,2].

Device migration and rare complications

On rare occasions, IUDs that perforate can migrate to the abdominal cavity and adhere to or injure adjacent organs. This is uncommon but may require surgical retrieval. Other rare complications include embedding of the device in the uterine wall, which can make removal more difficult and require hysteroscopic removal (ACOG; Cleveland Clinic) [1,4].

Symptoms that warrant prompt medical attention

Contact a clinician promptly if you experience any of the following after IUD insertion:

  • Severe or persistent abdominal/pelvic pain, fever, or chills (possible infection or perforation).
  • Heavy vaginal bleeding not controlled by usual measures.
  • An inability to feel IUD strings or feeling that the device has moved or been expelled.
  • Unusual or malodorous vaginal discharge.
  • Suspected pregnancy (missed period, pregnancy symptoms, or positive pregnancy test).

Early evaluation reduces the risk of complications and determines appropriate management (Mayo Clinic; ACOG) [1,2].

Impact on fertility and long-term health

One common concern is whether an IUD causes infertility. The evidence indicates that IUDs do not impair long-term fertility once the device is removed. Temporary delays in conception may occur related to the return of normal ovulation in some HORMONAL IUD users, but most individuals conceive within a year after removal. The historical association of IUDs and infertility largely stemmed from infections caused by earlier device designs and untreated STIs, not from modern devices themselves (ACOG; NIH) [1,3].

Long-term health effects are generally minimal. Levonorgestrel IUDs deliver progestin locally with low systemic exposure; systemic side effects such as mood changes or headaches may occur but are usually transient. Copper IUDs do not affect hormonal profiles but may cause heavier menstrual bleeding in some users (Mayo Clinic; Cleveland Clinic) [2,4].

Who is a good candidate — contraindications and considerations

IUDs are suitable for many people, including adolescents, nulliparous individuals (those who have not given birth), and those who have completed childbearing. Contraindications include:

  • Current pregnancy.
  • Known or suspected pelvic infection.
  • Active cervical or uterine cancer.
  • Unexplained abnormal uterine bleeding (until evaluated).
  • Certain uterine anomalies that prevent proper placement.

Relative contraindications and cautions include recent postpartum insertion (increased risk of expulsion and perforation if placed within a few weeks of delivery), a history of complicated gynecologic surgery, and current sexually transmitted infection without treatment. ACOG and other professional organizations provide detailed eligibility criteria and counseling points (ACOG; NIH) [1,3].

Counseling before insertion: informed decision-making

Effective counseling before insertion should include:

  • Discussion of effectiveness and alternative options (e.g., barrier methods, sterilization).
  • Review of expected side effects specific to copper vs. levonorgestrel IUDs.
  • Screening for STIs as indicated and pregnancy testing if clinically necessary.
  • Review of insertion procedure, pain management options, and possible complications.
  • Instructions for how to check strings and what to do if strings are not felt or symptoms develop.

Shared decision-making and provision of written materials helps ensure informed consent (ACOG; Mayo Clinic) [1,2].

What to expect during and after insertion

  • During insertion: Discomfort, cramping, and brief pain are common. Analgesia options include oral NSAIDs before the procedure, local cervical anesthesia, or procedural sedation in certain circumstances.
  • Immediately after: Short period of observation; light bleeding and cramping are typical. Resume routine activities as tolerated.
  • Follow-up: Many clinicians recommend a check after 4–12 weeks to ensure correct placement and to address concerns. Annual gynecologic care should include IUD assessment as part of routine reproductive health (Cleveland Clinic; Mayo Clinic) [2,4].

Removal and replacement

IUD removal is a simple office procedure. If pregnancy is desired, fertility typically returns rapidly after removal. Removal is recommended before expiry of the device’s labeled duration; removal and replacement can be performed at the same visit if continued contraception is desired. In cases of embedded or partially perforated devices, hysteroscopic or laparoscopic removal by a specialist may be necessary (ACOG; Mayo Clinic) [1,2].

Special situations

  • Postpartum and breastfeeding: IUDs can be inserted immediately postpartum or delayed; immediate postpartum insertion is convenient but has a higher expulsion rate. Levonorgestrel IUDs are considered safe during breastfeeding, with minimal effect on milk production (ACOG; NIH) [1,3].
  • Adolescents and nulliparous individuals: IUDs are appropriate for adolescents and those who have never given birth. Counseling should include information about insertion-related discomfort and follow-up (ACOG) [1].
  • History of ectopic pregnancy: IUDs reduce overall pregnancy risk; however, if pregnancy occurs with an IUD in place, relative likelihood of ectopic location is higher than in the general pregnant population. Individual risk assessment informs method choice (Mayo Clinic; ACOG) [1,2].

Myths and misconceptions

  • “IUDs cause systemic poisoning”: Modern IUDs are safe. Levonorgestrel exposure is primarily local, and copper IUDs do not release systemic toxins. Routine labs or detoxification are not required.
  • “IUDs cause permanent infertility”: There is no evidence that modern IUDs cause long-term infertility when properly managed.
  • “IUDs cause widespread infection”: The short-term risk of pelvic infection is slightly increased immediately after insertion if an STI is present, but long-term infection risk is low and comparable to non-IUD users when appropriate screening is performed (ACOG; NIH) [1,3].

Balancing benefits and risks

IUDs offer major benefits: high contraceptive effectiveness, convenience, cost-effectiveness over time, and, for levonorgestrel IUDs, substantial reductions in menstrual bleeding for many users. The primary safety concerns—expulsion, perforation, and early post-insertion infection—are uncommon, and many can be minimized by appropriate patient selection, STI screening, and trained providers performing insertions. Thorough counseling about expected side effects and warning signs improves user satisfaction and timely management of problems (ACOG; Cleveland Clinic; Mayo Clinic) [1,2,4].

When to seek care

Seek clinical evaluation if you experience:

  • Severe pelvic or abdominal pain, fever, or heavy bleeding.
  • Inability to feel IUD strings or suspicion the device has moved or been expelled.
  • Positive pregnancy test with an IUD in place.
  • Foul-smelling or purulent vaginal discharge.

Early attention allows treatment of infection, removal of malpositioned devices, and appropriate pregnancy management if needed (Mayo Clinic; ACOG) [1,2].

Practical tips for IUD users

  • Learn how to check the IUD strings and do so at intervals recommended by your clinician; do not pull the strings.
  • Use condoms if you are at risk for STIs; IUDs do not protect against infections.
  • Keep routine follow-up appointments and seek care if symptoms emerge.
  • Inform clinicians about the IUD before pelvic imaging or gynecologic procedures.

Conclusion

Modern IUDs are a safe, highly effective, long-acting contraceptive option for many people. Serious complications are rare, but awareness of possible problems — including expulsion, perforation, infection, changes in bleeding patterns, and very rare migration — is important for informed consent and prompt management. Proper patient selection, STI screening, skilled insertion, and clear counseling reduce the likelihood of adverse outcomes. When used appropriately and followed clinically, the benefits of IUDs typically outweigh the risks for those seeking reliable reversible contraception.

References

  • American College of Obstetricians and Gynecologists (ACOG). Intrauterine Devices (IUDs). Patient FAQ. https://www.acog.org/womens-health/faqs/intrauterine-devices-iuds (accessed 2026).
  • Mayo Clinic. IUD: Types, uses, side effects. https://www.mayoclinic.org/tests-procedures/iud/about/pac-20384719 (accessed 2026).
  • National Institute of Child Health and Human Development (NICHD/NIH). Contraception Methods: IUD. https://www.nichd.nih.gov/health/topics/contraception/conditioninfo/iud (accessed 2026).
  • Cleveland Clinic. Intrauterine Device (IUD): Types & Side Effects. https://my.clevelandclinic.org/health/treatments/9125-contraceptive-iud (accessed 2026).

(For more detailed practice recommendations, consult full ACOG practice bulletins and clinical guidance documents.)