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Intrauterine Device (IUDs; IUD)

By

Frances E. Casey

, MD, MPH, Virginia Commonwealth University Medical Center

Last full review/revision Feb 2022
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In the US, 12% of women who use contraception use intrauterine devices (IUDs); IUDs are popular because of their advantages as a contraceptive method:

  • IUDs are highly effective.

  • IUDs have minimal systemic effects.

  • IUDs need to be changed only every 3, 5, 7, or 10 years, avoiding the need to use a daily, weekly, or monthly contraceptive method.

In the US, available IUDs include levonorgestrel-releasing IUDs and a copper-bearing IUD.

Levonorgestrel-releasing IUDs include

  • 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%.

  • 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 IUDs contain 52 mg (20 mcg a day for 5 years, 10 mcg a day after 5 years) were originally used for 5 years with a cumulative 5-year pregnancy rate of 0.5 to 1.1%; additional studies report them to be effective at 7 years with a cumulative 7-year pregnancy rate of 0.5 to 1.1%. Use for 8 years is being evaluated.

The copper-bearing T380A IUD is effective for 10 years; it has a cumulative 12-year pregnancy rate of < 2% (see table Comparison of Intrauterine Devices Comparison of Intrauterine Devices Comparison of Intrauterine Devices ).

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 Overview of Sexually Transmitted Infections Sexually transmitted infections (STIs), also termed sexually transmitted diseases or STDs, can be caused by a number of microorganisms that vary widely in size, life cycle, the diseases and... read more (STIs)—gonorrhea and chlamydial infection—should be done just before the IUD is inserted. 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 reviewed before insertion. 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 ( 1 Insertion references In the US, 12% of women who use contraception use intrauterine devices (IUDs); IUDs are popular because of their advantages as a contraceptive method: IUDs are highly effective. IUDs have minimal... read more ).

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 ( 2 Insertion references In the US, 12% of women who use contraception use intrauterine devices (IUDs); IUDs are popular because of their advantages as a contraceptive method: IUDs are highly effective. IUDs have minimal... read more ).

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.

Insertion references

  • 1. 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

  • 2. 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

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/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

Vaginal bleeding is often irregular in the first several months after insertion of a levonorgestrel-releasing IUD. Bleeding then stops completely within 1 year in up to 20% of women; some patients consider this effect a benefit of the IUD.

A copper-bearing T380A IUD may cause heavier menstrual bleeding and more severe cramping, which can be relieved by nonsteroidal anti-inflammatory drugs (NSAIDs; eg, ibuprofen).

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

Levonorgestrel-releasing IUDs are associated with a decreased risk of endometrial cancer and ovarian cancer. Data about whether they increase the risk of breast cancer are conflicting ( 1 Potential benefits reference In the US, 12% of women who use contraception use intrauterine devices (IUDs); IUDs are popular because of their advantages as a contraceptive method: IUDs are highly effective. IUDs have minimal... read more ).

Potential benefits reference

  • 1. 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

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

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 Ectopic Pregnancy In ectopic pregnancy, implantation occurs in a site other than the endometrial lining of the uterine cavity—ie, in the fallopian tube, uterine cornua, cervix, ovary, or abdominal or pelvic cavity... read more 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.

Key Points

  • IUDs are highly effective contraceptives and have minimal systemic effects, and IUDs need to be changed only every 3, 5, 7 or 10 years depending on the IUD chosen.

  • Types include levonorgestrel-releasing IUDs (effective for 3 to 7 years, depending on the type) and a copper-bearing IUD (effective for 10 years, with a 12-year pregnancy rate of < 2%).

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

  • Inform women that both types of IUDs can affect menstrual bleeding (amenorrhea with levonorgestrel-releasing IUDs and possibly heavier menstrual bleeding and more severe cramping with the copper-bearing 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.

Drugs Mentioned In This Article

Drug Name Select Trade
MIRENA, PLAN B
ADVIL, MOTRIN IB
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