Reproductive · Contraception
The facts most likely to be tested
Levonorgestrel IUDs are the first-line treatment for heavy menstrual bleeding and endometrial hyperplasia due to their local progestin-induced endometrial atrophy.
Copper IUDs are the most effective form of emergency contraception if inserted within 5 days of unprotected intercourse.
Actinomyces israelii colonization, characterized by sulfur granules on Pap smear, is a common incidental finding in asymptomatic IUD users and does not require removal or antibiotics.
Uterine perforation is the most serious complication of IUD insertion, typically presenting with missing strings and severe pelvic pain.
Pregnancy occurring with an IUD in situ carries a significantly increased risk of ectopic pregnancy, necessitating immediate ultrasound evaluation.
Pelvic Inflammatory Disease (PID) risk is highest only in the first 21 days post-insertion, after which the IUD does not increase the risk of infection.
Copper IUDs are contraindicated in patients with Wilson disease due to the potential for systemic copper accumulation.
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A 28-year-old G2P2 woman presents to the clinic for a routine follow-up. She had a levonorgestrel-releasing IUD placed 6 months ago for contraception and management of menorrhagia. She reports that her periods have become significantly lighter, but she is concerned because she cannot feel her IUD strings during self-examination. On pelvic exam, the cervix is closed and no strings are visualized at the external os. A transvaginal ultrasound is performed, which shows the IUD is not within the uterine cavity.
What is the most appropriate next step in management?
Abdominal and pelvic X-ray or CT scan
The patient has a suspected uterine perforation with an extrauterine IUD; imaging is required to locate the device to prevent bowel or bladder injury.
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Etiology / Epidemiology
Highly effective long-acting reversible contraception (LARC). Indicated for patients desiring long-term pregnancy prevention or management of menorrhagia.
Clinical Manifestations
Patients may report string visualization or cramping. Spontaneous expulsion is most common in the first 3 months.
Diagnosis
Transvaginal ultrasound (TVUS) is the gold standard to confirm intrauterine placement.
Treatment
Levonorgestrel IUD is first-line for menorrhagia. Contraindications include active pelvic infection or uterine anomalies.
Prognosis
Failure rate is <1%. Uterine perforation is a rare but serious surgical emergency.
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Epidemiology & Etiology
IUDs are the most effective reversible contraceptives, with failure rates comparable to sterilization. They are ideal for patients seeking long-term compliance without daily administration. Candidates must be screened for current STI or cervical cancer prior to insertion.
Pertinent Anatomy
The device is placed within the uterine cavity via the cervical os. Proper placement requires the device to be positioned at the uterine fundus. The strings extend through the cervix to allow for verification and removal.
Pathophysiology
Copper IUDs induce a sterile inflammatory response that is toxic to sperm and ova. Levonorgestrel IUDs cause cervical mucus thickening and endometrial atrophy, preventing fertilization and implantation. These mechanisms are entirely reversible upon device removal.
Clinical Manifestations
Common complaints include spotting or irregular bleeding, especially with levonorgestrel systems. Patients may present with missing strings on exam, raising concern for malposition or expulsion. Severe pelvic pain or fever suggests pelvic inflammatory disease (PID) or uterine perforation.
Diagnosis
Transvaginal ultrasound (TVUS) is the gold standard for locating a missing IUD. If the device is not visualized in the uterus, an abdominal/pelvic X-ray is required to rule out extrauterine migration into the peritoneal cavity.
Treatment
Levonorgestrel IUDs are first-line for heavy menstrual bleeding. Copper IUDs are the most effective emergency contraception if placed within 5 days of unprotected intercourse. Contraindications include pregnancy, distorted uterine cavity, and active breast cancer (for hormonal IUDs).
Prognosis
The Pearl Index for IUDs is <1, indicating high efficacy. Uterine perforation occurs in approximately 1/1000 insertions. Patients should be counseled to check for strings monthly to ensure proper placement.
Differential Diagnosis
Ectopic pregnancy: positive hCG with empty uterus
Pelvic Inflammatory Disease: cervical motion tenderness
Endometrial polyp: intermenstrual bleeding with normal TVUS
Uterine fibroids: enlarged, irregular uterus on exam
Cervical cancer: postcoital bleeding and abnormal Pap