Extrauterine IUD

54-year-old female with an Incidental Finding • Xray of the Week

Name the device and location.

Figure 1. CT scan of the abdomen and pelvis.

Figure 2. CT scan of the abdomen and pelvis. A: Axial view of the pelvis showing the extrauterine IUD located in the right lower quadrant (orange arrow) and the normal uterus (green arrow). B: Sagittal oblique view of the abdomen and pelvis displaying the IUD (orange arrow) superior to the bladder dome and inferior to the uterus. C: Sagittal view of the abdomen and pelvis displaying a normal anteflexed uterus (green arrow). The IUD is not visible in this view and is clearly not in the endometrial canal.

Discussion:

Intrauterine devices (IUD) are a form of long-acting contraception designed to be inserted into the uterine cavity. Examples include the copper IUD, which can be used for up to 10 years, and the levonorgestrel IUD, which can be used for up to 5 years [1]. The copper IUD functions by acting as a spermicidal agent via a local inflammatory response to the copper material [1]. The levonorgestrel IUD functions by thickening the cervical mucus, which impairs sperm penetration and subsequent fertilization [2]. In women over 35, the copper IUD can be effective for more than 10 years [3]. The main complication during or after IUD insertion is total or partial uterine perforation. A prospective cohort study published in 2013 identified an overall uterine perforation rate of 1.6 per 1000 insertions for copper IUD users and 2.1 per 1000 insertions for levonorgestrel IUD users [4]. One-third of perforations were detected at 12 months after insertion [4]. Most IUDs that become intra-abdominal are associated with complete uterine perforations [5].

If the strings of the IUD are not visible during a pelvic exam, ultrasound is the preferred method of locating the IUD in the uterus. While transabdominal and transvaginal approaches can both be used, transvaginal ultrasounds provide better resolution [5]. An IUD is ideally visualized on transabdominal ultrasound when the uterus is at a 90-degree angle in an anteflexed position [5]. IUDs are identified by their echogenic appearance relative to uterine tissue (Figs. 1,2). If the ultrasound confirms that the IUD is no longer intrauterine, the next step is to obtain an abdominal radiograph or CT scan to determine the exact location of the device (Figs. 1,2).

Studies have shown that half of all cases of extrauterine IUDs causing bowel perforations were due to copper IUDs [6]. The most common presenting symptom was abdominal pain (55%), although 38% of patients were asymptomatic at the time of diagnosis [6]. In order of prevalence, the most commonly perforated regions are the sigmoid colon, small bowel, and rectum [6]. Given the risk of colon perforation and other complications, surgical removal of extrauterine IUDs via laparoscopy or laparotomy is recommended [6]. However, some studies suggest that surgical removal of asymptomatic extrauterine IUDs is unnecessary because the development of adhesions around the misplaced IUD prevents further migration and damage from the IUD [8, 9].

References:

1. Bahamondes L, Fernandes A, Monteiro I, Bahamondes MV. Long-acting reversible contraceptive (LARCs) methods. Best Pract Res Clin Obstet Gynaecol. 2020;66:28-40. doi:10.1016/j.bpobgyn.2019.12.002

2. Moraes LG, Marchi NM, Pitoli AC, et al. Assessment of the quality of cervical mucus among users of the levonorgestrel-releasing intrauterine system at different times of use. European Journal of Contraception & Reproductive Health Care. 2016;21(4):318-322. doi:10.1080/13625187.2016.1193139

3. Bahamondes L, Faundes A, Sobreira-Lima B, Lui-Filho JF, Pecci P, Matera S. TCu 380A IUD: a reversible permanent contraceptive method in women over 35 years of age. Contraception. 2005;72(5):337-341. doi:10.1016/j.contraception.2004.12.026

4. Barnett C, Moehner S, Do Minh T, Heinemann K. Perforation risk and intra-uterine devices: results of the EURAS-IUD 5-year extension study. Eur J Contracept Reprod Health Care. 2017;22(6):424-428. doi:10.1080/13625187.2017.1412427

5. Carmody K, Schwartz B, Chang A. Extrauterine migration of a mirena® intrauterine device: a case report. J Emerg Med. 2011;41(2):161-165. doi:10.1016/j.jemermed.2010.04.024

6. Arslan A, Kanat-Pektas M, Yesilyurt H, Bilge U. Colon penetration by a copper intrauterine device: a case report with literature review. Arch Gynecol Obstet. 2009;279(3):395-397. doi:10.1007/s00404-008-0716-2

7. Inal HA, Ozturk Inal Z, Alkan E. Successful Conservative Management of a Dislocated IUD. Case Rep Obstet Gynecol. 2015;2015:130528. doi:10.1155/2015/130528

8. Markovitch O, Klein Z, Gidoni Y, Holzinger M, Beyth Y. Extrauterine mislocated IUD: is surgical removal mandatory?. Contraception. 2002;66(2):105-108. doi:10.1016/s0010-7824(02)00327-x

9. Adoni A, Ben Chetrit A. The management of intrauterine devices following uterine perforation. Contraception. 1991;43(1):77-81. doi:10.1016/0010-7824(91)90128-3

Leslie Shang is a 6th-year medical student at the University of Missouri – Kansas City Six-Year BA/MD Program and an aspiring radiologist. At UMKC, she serves as the social media coordinator of the Radiology Interest Group. She is also the vice president of the Help a Life Organization (HALO) which serves free meals to patients at the student-run free clinic and provides educational lectures to students on healthy eating and diet counseling for patients. In her free time, she enjoys exploring new restaurants in Kansas City, hiking, and spending time with friends.

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Kevin M. Rice, MD is the president of Global Radiology CME

Dr. Rice is a radiologist with Renaissance Imaging Medical Associates and is currently the Vice Chief of Staff at Valley Presbyterian Hospital in Los Angeles, California. Dr. Rice has made several media appearances as part of his ongoing commitment to public education. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. In 2015, Dr. Rice and Natalie Rice founded Global Radiology CME to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. In 2016, Dr. Rice was nominated and became a semifinalist for a "Minnie" Award for the Most Effective Radiology Educator.

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