Intrauterine Device (IUDs; IUD)

ByFrances E. Casey, MD, MPH, Virginia Commonwealth University Medical Center
Reviewed/Revised Jul 2023
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In the United States, 12% of women who use contraception use intrauterine devices (IUDs). IUDs are popular because of their advantages as a contraceptive method, including being highly effective and having minimal side effects. Also, IUDs need to be changed only every 3, 5, 8, or 10 years, avoiding the need to use a daily, weekly, or monthly contraceptive method.

  • A 13.5-mg IUD (14 mcg a day) is effective for 3 years and has a 3-year cumulative pregnancy rate of 1.0% (1).

  • A 19.5-mg IUD (17.5 mcg a day) is effective for 5 years and has a cumulative 5-year pregnancy rate of 0.9 to 1.4%.

  • Two 52 mg IUDs (20 mcg a day initially, declining to 10 mcg a day after 5 years) are effective for 8 years with a cumulative 8-year pregnancy rate of 0.5 to 1.1% (2, 3).

The intrauterine copper contraceptive is effective for 10 years; it has a cumulative 12-year pregnancy rate of < 2% (4). See table Comparison of Intrauterine Devices.

Table
Table

Insertion of the IUD

Clinicians do not need to do a Papanicolaou (Pap) test or human papillomavirus (HPV) test before they insert an IUD, unless the patient is due for cervical cancer screening. Testing for sexually transmitted infections (STIs)—gonorrhea and chlamydia—prior to IUD insertion should be based on "risk-based" screening (age ≤ 25 years, multiple sexual partners, inconsistent condom use, and/or history of a STI) (5). However, clinicians do not need to wait for results of STI testing before they insert an IUD. If results are positive, patients should be treated with appropriate antibiotics; the IUD is left in place. If purulent cervical discharge is observed just before planned IUD insertion, the IUD is not inserted and STI testing is done; the infection, if present, is then treated, and the IUD is inserted after treatment of the infection is complete.

The package insert for the IUD should be read before insertion to review the insertion technique. When IUDs are inserted, sterile technique is used as much as possible. Bimanual examination should be done to determine the position of the uterus and a tenaculum should be placed on the anterior lip of the cervix to stabilize the uterus, straighten the uterine axis, and help ensure correct placement of the IUD. A uterine sound device may be used to measure the length of the uterine cavity before IUD insertion. Before insertion, a paracervical block may be used to decrease pain during insertion (6).

An IUD may be inserted at any time during the menstrual cycle if a woman has not had unprotected intercourse during the past month.

A routine follow-up visit after IUD insertion is not necessary. Patients should be counseled to return for evaluation if they experience symptoms or complications (eg, pain, heavy bleeding, abnormal vaginal discharge, fever, expulsion) or are dissatisfied with the method (7).

An IUD may be inserted immediately after an induced or a spontaneous abortion during the 1st or 2nd trimester and immediately after delivery of the placenta in a cesarean or vaginal delivery.

Contraindications

Most women can use an IUD. Contraindications include the following:

Conditions that do not contraindicate IUDs include the following:

  • Contraindications to contraceptives that contain estrogen (eg, history of venous thromboembolism, smoking > 15 cigarettes a day in women > 35, migraine with aura, migraine of any type in women > 35)

  • A history of PID, STIs, or ectopic pregnancy

  • Breastfeeding

  • Adolescence

  • The patient's personal beliefs about abortion because IUDs are not abortifacients (however, a copper or 52-mg levonorgestrel-releasing IUD used for emergency contraception may prevent implantation of the blastocyst, possibly terminating a viable pregnancy)

Adverse effects

Women should be told about these effects before the IUD is inserted because this information may help them decide which type of IUD to choose.

Potential benefits

Complications

Average IUD expulsion rates are usually < 5% within the first year after insertion; however, expulsion rates are higher if the IUD is inserted immediately (< 10 minutes) after a delivery. After insertion, a clinician confirms correct placement at 6 weeks by looking for the strings attached to the IUD, which are typically trimmed to 3 cm from the external cervical os.

The uterus is perforated in about 1/1000 IUD insertions. Perforation typically occurs at the time of IUD insertion. Sometimes only the distal part of the IUD penetrates; then over the next few months, uterine contractions force the IUD into the peritoneal cavity. If the strings are not visible during pelvic examination, clinicians may do one or more of the following:

  • Use a cytobrush to attempt to sweep the strings out of the cervical canal

  • Gently probe the uterine cavity with an IUD hook, sound, or biopsy instrument (unless pregnancy is suspected), being careful not to push the IUD further into the uterine cavity or myometrium

  • Do ultrasonography; alligator forceps may be used under sonographic guidance (9)

If the IUD is not seen, an abdominal x-ray is taken to exclude an intraperitoneal location. Intraperitoneal IUDs may cause intestinal adhesions. IUDs that have perforated the uterus are removed via laparoscopy.

If expulsion or perforation is suspected, a backup contraceptive method should be used.

Rarely, salpingitis (pelvic inflammatory disease [PID]) develops during the first month after insertion because bacteria are displaced into the uterine cavity during insertion; however, this risk is low and routine antibiotic prophylaxis is not indicated. If PID develops, antibiotics should be given. The IUD need not be removed unless the infection persists despite antibiotics. IUD strings do not provide access for bacteria. Except during the first month after insertion, IUDs do not increase the risk of pelvic inflammatory disease.

If Actinomyces-like organisms on a Pap test in women with no symptoms of infection does not require antibiotics nor IUD removal.

The incidence of ectopic pregnancy is much lower in IUD users than in women using no contraceptive method because IUDs effectively prevent pregnancy. However, if a women becomes pregnant while an IUD is in place, she should be told that risk of ectopic pregnancy is increased, and she should be evaluated promptly.

References

  1. 1. Nelson A, Apter D, Hauck B, et al: Two low-dose levonorgestrel intrauterine contraceptive systems: a randomized controlled trial [published correction appears in Obstet Gynecol 123(5):1109, 2014]. Obstet Gynecol 122(6):1205-1213, 2013. doi:10.1097/AOG.0000000000000019

  2. 2. Jensen JT, Lukkari-Lax E, Schulze A, et al: Contraceptive efficacy and safety of the 52-mg levonorgestrel intrauterine system for up to 8 years: findings from the Mirena Extension Trial. Am J Obstet Gynecol 227(6):873.e1-873.e12, 2022. doi:10.1016/j.ajog.2022.09.007

  3. 3. Creinin MD, Schreiber CA, Turok DK, et al: Levonorgestrel 52 mg intrauterine system efficacy and safety through 8 years of use. Am J Obstet Gynecol 227(6):871.e1-871.e7, 2022. doi:10.1016/j.ajog.2022.05.022

  4. 4. Long-term reversible contraception. Twelve years of experience with the TCu380A and TCu220C. Contraception 56(6):341-352, 1997.

  5. 5. Grentzer JM, Peipert JF, Zhao Q, et al: Risk-based screening for Chlamydia trachomatis and Neisseria gonorrhoeae prior to intrauterine device insertion. Contraception 92(4):313-318, 2015. doi:10.1016/j.contraception.2015.06.012

  6. 6. Mody SK, Farala JP, Jimenez B, et al: Paracervical block for intrauterine device placement among nulliparous women: A randomized controlled trial, Obstet Gynecol 132 (3): 575–582, 2018. doi: 10.1097/AOG.0000000000002790

  7. 7. Curtis KM, Jatlaoui TC, Tepper NK, et al: U.S. Selected Practice Recommendations for Contraceptive Use, 2016. MMWR Recomm Rep 65 (4):1–66, 2016. doi: 10.15585/mmwr.rr6504a1

  8. 8. Jareid M, Thalabard JC, Aarflot M, et al: Levonorgestrel-releasing intrauterine system use is associated with a decreased risk of ovarian and endometrial cancer, without increased risk of breast cancer: Results from the NOWAC Study. Gynecol Oncol 149 (1), 127–132, 2018, doi.org/10.1016/j.ygyno.2018.02.006

  9. 9. Prabhakaran S, Chuang A: In-office retrieval of intrauterine contraceptive devices with missing strings. Contraception 83(2):102-106, 2011. doi:10.1016/j.contraception.2010.07.004

Key Points

  • IUDs are highly effective contraceptives and have minimal systemic effects, and IUDs need to be changed only every 3, 5, 8, or 10 years depending on the IUD chosen.

  • A Pap or HPV test is not required before IUD insertion unless the patient is due for cervical cancer screening.

  • copper T380 IUD).

  • Counsel patients to return for evaluation after IUD placement if they have complications (eg, pain, heavy bleeding, abnormal vaginal discharge, fever, expulsion).

  • If the strings are not visible during the pelvic examination, attempt to sweep the strings out with a cytobrush or gently probe the uterine cavity using an IUD hook, uterine sound, or biopsy instrument (unless pregnancy is suspected), and if needed, do ultrasonography or take an abdominal x-ray to check for location.

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