Intrauterine devices in early pregnancy: findings on ultrasound and clinical outcomes Elysia Moschos, MD; Diane M. Twickler, MD

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1 Research OBSTETRICS Intrauterine devices in early pregnancy: findings on ultrasound and clinical outcomes Elysia Moschos, MD; Diane M. Twickler, MD OBJECTIVE: The objective of this study was to describe ultrasound findings, clinical symptoms, and outcomes of first-trimester pregnancies with intrauterine devices (IUDs). STUDY DESIGN: This was a retrospective review of 42 women with history of IUD placement and positive serum human chorionic gonadotropin in the first trimester. RESULTS: There were 31 intrauterine pregnancies (IUPs), 3 ectopic pregnancies, and 8 pregnancies of unknown location. Of 36 IUDs visualized, 15 were normally positioned and 21 malpositioned. Of 31 IUPs, 8 IUDs were within the endometrium, 17 were malpositioned, and 6 were not seen. Indications included bleeding (14 of 31), pain (12 of 31), and missing strings (5 of 31); 11 had no symptoms. Of 26 IUPs with known pregnancy outcomes, 20 were term deliveries and 6 had failed pregnancies of 20 weeks or less. CONCLUSION: More than half of IUDs identified in the first trimester were malpositioned. IUP was 3 times as likely with a malpositioned or missing IUD. Three quarters of the IUPs with known outcomes had term deliveries. Symptoms were not predictive of IUD malposition. Key words: complications of intrauterine devices, intrauterine device, intrauterine device in pregnancy Cite this article as: Moschos E, Twickler DM. Intrauterine devices in early pregnancy: findings on ultrasound and clinical outcomes. Am J Obstet Gynecol 2011;204:427.e1-6. Although the intrauterine device (IUD) is a highly effective form of birth control, complications, including pregnancy, do occur. 1 Long-term cumulative pregnancy rates with IUD use are extremely low but vary slightly with the IUD type: per 100 women for the copper containing ParaGard T 380A (Duramed Pharmaceuticals, Inc, Montvale, NJ) 2,3 and per 100 women for the levonorgestrel-releasing Mirena From the Division of Gynecology, Department of Obstetrics and Gynecology (both authors), and the Department of Radiology (Dr Twickler), University of Texas Southwestern Medical Center, Dallas, TX. Presented as an oral scientific clinical gynecology sonography session at the Annual Convention of the American Institute of Ultrasound in Medicine, San Diego, CA, March 24-27, Received Aug. 31, 2010; revised Dec. 6, 2010; accepted Dec. 29, Reprints: Elysia Moschos, MD, University of Texas Southwestern Medical Center, Department of Obstetrics and Gynecology, 5323 Harry Hines Blvd., Dallas, TX elysia.moschos@utsouthwestern.edu /$ Mosby, Inc. All rights reserved. doi: /j.ajog (Bayer Schering Pharma Oy, Turku, Finland). 2,4 Timely evaluation of the pregnant woman with an IUD is important in an effort to reduce subsequent complications if the woman chooses to continue her pregnancy. Evaluation typically includes transvaginal sonography to establish the pregnancy location and to identify IUD position and retrievability. 5 The purpose of our study was to describe the ultrasound findings, clinical characteristics, and pregnancy outcomes of first-trimester pregnancies with IUDs. MATERIALS AND METHODS From July 1, 2008, through June 30, 2009, a retrospective review of our ultrasound database was performed for women with history of IUD placement and a positive serum beta-human chorionic gonadotropin. Ultrasound images and reports were reviewed for identification and location of pregnancy, identification, type and position of IUD, and presenting symptoms. Outcomes of the pregnancies were reviewed. All ultrasound procedures were performed in the obstetrics and gynecology ultrasound unit at our county-based teaching hospital. The study was approved by our institutional review board (# ). The 2-dimensional (2D) and/or 3-dimensional (3D) images of the uterine cavities were obtained with an Antares (Siemens, Redmond, WA), an Elegra (Siemens), or a Voluson 730 (General Electric Medical Systems, Milwaukee, WI) scanner and 5 MHz or multifrequency transvaginal transducers. The method of coronal view reconstruction was derived from the Z-plane technique as described by Abuhamad et al. 6 The location of the pregnancy was determined to be either intrauterine, as defined by the minimum criteria of a double decidual sign within the endometrial cavity, ectopic (no gestational sac within the uterus and an adnexal mass), or pregnancy of unknown location (PUL). The IUD position was considered to be appropriately endometrial if both the arms and shaft were seen within the fundal or midportion of the cavity (Figure 1). The IUD was considered malpositioned if any part extended into the lower uterine segment, myometrium, or endocervical canal, as depicted in Figure 2, A and B. Statistical significance was established at a P.05 for the analyses. A Fisher s exact test was used to test the data from 2 independent variables consisting of the measurements classified above. All tests MAY 2011 American Journal of Obstetrics & Gynecology 427.e1

2 Research Obstetrics FIGURE 1 Properly positioned copper IUD Both arms and shaft are seen within the fundal or midportion of the cavity in this coronal 3D image. An IUP, as evidenced by a gestational sac containing a yolk sac, is seen adjacent to the IUD. IUD, intrauterine device; IUP, intrauterine pregnancy. were performed using SAS version 9.2 (SAS Institute, Cary, NC). RESULTS As a reference, 4157 IUDs were placed in our health care system from July 1, 2008, through June 30, Forty-two patients with biochemical or sonographic evidence of pregnancy and history of IUD placement were evaluated. The principal race/ethnicity of our patient population was Hispanic (36 of 42 or 85%), followed by equal numbers of African or African American (2 of 42 or 5%), white (2 of 42 or 5%), and other ethnicities (2 of 42 or 5%). The patients were multiparous, with a mean gravidity of 3 (range, 2 7) pregnancies and a mean parity of 2 (range, 1 5) deliveries. The mean age was 26 years (range, years). Data on the time of IUD usage were available in 32 of the 42 patients, with an average of 24.7 months (range, 2 60 months). The mean estimated gestational age at presentation and diagnosis of pregnancy and IUD location was 8.0 weeks (range, weeks). Of these 42 patients, 31 (74%) had intrauterine pregnancies, 3 (7%) had ectopic pregnancies, and 8 (19%) were diagnosed with PUL. The most common type of IUD was the copper T 380A or ParaGard (30 of 42 or 72%) (Figure 1), followed by the levonorgestrel-containing IUD or Mirena (5 of 42 or 12%) and 1 Lippes loops (2%) (Figure 3). The distribution of IUD types in this series of gravid patients was similar to that in our nongravid population in a series of symptomatic women. 7 Of the 36 IUDs seen, 15 patients (42%) had IUDs within the endometrial cavity and 21 patients (58%) had malpositioned IUDs. In all cases, the determination of IUD type and location was made on the initial sonographic evaluation by 2D ultrasound, and in 6 patients in whom 2D imaging was equivocal, 3D imaging was performed to confirm the diagnosis. Among the 31 intrauterine pregnancies (IUPs), 8 (26%) had IUDs within the endometrial cavity (Figure 1), 17 (55%) had malpositioned IUDs (Figure 2, A and B), and 6 (19%) had expelled their IUDs as described above. In all 3 ectopic pregnancy patients, an appropriately positioned copper IUD was visualized, as shown in Figure 4, A and B. Ofthe PULs, 5 IUDs (62.5%) were within the endometrium and 3 (37.5%) were malpositioned. Pregnancy outcomes were known in 37 of 42 cases (88%). All 8 pregnancies of unknown location resulted in spontaneous abortions. The 3 ectopic pregnancies were successfully treated; 2 received methotrexate and the third underwent a laparoscopic salpingectomy for rupture of the tubal pregnancy. The Table depicts the intrauterine pregnancy outcomes as they related to sonographic findings. Of 31 intrauterine pregnancies, 5 (16%) were lost to follow-up and outcomes were available in the remaining 26 women (84%), who all desired to continue their pregnancies. Twenty of these women (20 of 26 or 77%) had successful term live births. Among these 20 women, half (10) elected to have their IUDs removed, no IUD was identified in 5 patients, 1 IUD was left in situ because the strings were not visible (the IUD was later discovered in the placenta at delivery), and in 4 patients, no data were available regarding whether their IUD remained in situ or was removed. Unfortunately, 6 of the 26 IUPs (23%) ended in pregnancy loss. One patient could not have her IUD removed from the endometrial cavity because the strings were not visible; she had a firsttrimester spontaneous abortion shortly thereafter. Three other patients consented to having their IUDs removed but still subsequently suffered first-trimester spontaneous abortions. A fifth patient, with an embedded IUD in the posterior myometrium, experienced premature rupture of membranes at weeks and subsequently aborted. The sixth patient, whose endometrial IUD was also left in situ from nonvisible strings, had an intrauterine fetal demise at 20 weeks. Fetal autopsy revealed that this fetus 427.e2 American Journal of Obstetrics & Gynecology MAY 2011

3 Obstetrics Research FIGURE 2 Malpositioned IUD symptoms and the remaining one quarter (11 of 42) had no symptoms. Vaginal bleeding (14 of 31 or 45%) was the most common indication, with almost half of patients complaining of this symptom, followed by pelvic pain (12 of 31 or 39%) and missing strings (5 of 31 or 16%). We then analyzed the presenting symptom as it related to IUD location. Although bleeding was the most common symptom in our patient population, less than half (6 of 14 or 43%) had malpositioned IUDs. A similar percentage of patients with missing strings had malpositioned IUDs (2 of 5 or 40%). Whereas just less than 40% of patients complained of pain, three quarters of those patients (9 of 12 or 75%) had abnormally located IUDs. However, these differences were not statistically significant (P.05). A, This sagittal transabdominal image demonstrates an IUP with the malpositioned IUD (arrow) in the cervix. B, Sagittaltransvaginalimageofthesamepatient, illustratingthemalpositionediud(arrow) intheendocervicalcanal. IUD, intrauterine device; IUP, intrauterine pregnancy. had Verma Naumoff short rib polydactyly syndrome, a rare lethal syndrome characterized by abnormal skeleton formation resulting in extra digits, short ribs, short limbs, and genital anomalies. Of the 42 pregnant patients, almost three quarters (31 of 42) presented with COMMENT The mechanisms of action of IUDs are thought to be multifactorial and are primarily aimed at preventing fertilization. The fundamental contraceptive mechanism is the production of a hostile, spermicidal intrauterine environment. The presence of the foreign IUD in the endometrial cavity creates a sterile but intense local inflammatory response that leads to lysosomal activation and other inflammatory actions that are spermicidal, especially with copper IUDs. 8,9 The copper IUD also releases free copper and copper salts that not only affect the endometrial environment but also cause alterations in cervical mucus, which are spermicidal. 10 If fertilization occurs, the same inflammatory actions are directed against the blastocyst. The progesterone-releasing IUDs are thought to have 2 principal modes of contraceptive action. In addition to the foreign body reaction, the endometrium also becomes atrophic secondary to the progestin, which further inhibits implantation. 11 Second, authors have shown that the progestin prevents fertilization by spermicidal action and interfering with sperm capacitation. 8,9 The progestin is also thought to interfere with sperm penetration through thickened cervical mucus. Ovarian fol- MAY 2011 American Journal of Obstetrics & Gynecology 427.e3

4 Research Obstetrics FIGURE 3 Lippes loop IUD In this sagittal transvaginal image, the IUD (arrow) is seen next to the gestational sac within the endometrial cavity. IUD, intrauterine device. licular development and ovulation are also partially inhibited but not consistently. 12,13 In the unlikely event that pregnancy occurs, it is more common to occur within the first year, presumably secondary to the higher incidence of displacement or expulsion of an IUD during that time period. 1 Data on the time of IUD usage were available in 32 of the 42 patients. Interestingly, the average length of time the IUD had been in place prior to pregnancy in our series was longer than expected, at just over 2 years. As one might anticipate and consistent with other reports, 14,15 a displaced or expelled IUD was noted in the majority of our pregnancies. In our series, less than half of IUDs were properly positioned and among the 31 IUPs, only one fourth had IUDs within the endometrial cavity. Because it is not standard of care in our institution to follow up IUD placement with sonographic surveillance, it is unclear whether these IUDs were malpositioned initially after placement or whether displacement occurred over time. As a direct result of this study, we are now contemplating a protocol implementing sonographic imaging after placement of IUDs to confirm proper positioning. When pregnancy is complicated by an IUD, early identification of the pregnancy and IUD location is important. In fact, the World Health Organization has a recommended protocol for a pregnancy complicated by an IUD, 16 which details these steps. Their first recommendation is to exclude ectopic pregnancy. In our series, pregnancy location could not be confirmed on initial imaging in approximately one fifth of patients, and all of these PULs were ultimately diagnosed as spontaneous abortions. Only 3 (of 42 or 7%) of our patients were diagnosed with ectopic pregnancies on their initial sonograms, and this incidence is consistent with the literature. 17 All of the ectopic pregnancies had properly positioned copper IUDs within the endometrial cavity (Figure 4, A and B). The remaining 75% of patients were documented to have IUPs. With regard to the second step, IUD localization, 2D imaging was the primary technique used in our series. The vast majority of our patients were assessed in our obstetrical women s emergency department, and for most of the study time period, only 2D ultrasound probes were available in that setting. Once 3D ultrasound probes were available in the emergency center, 3D imaging was reserved for patients with equivocal 2D findings. Three-dimensional ultrasound has now been shown in the literature to be more clinically useful, both in position assessment because it can locate the IUD in the volume of the endometrium in the coronal view, and in IUD type identification, particularly with the Mirena. 7,18-20 Subsequently it is now the standard of care in our sonography units to perform both a standard 2D ultrasound evaluation and a 3D volume acquisition to establish the type and positioning of an IUD in gravid and nongravid patients. Incidentally, 6 patients who had IUDs by history but in whom no IUD was identified on sonographic imaging were not discussed in the results of this series. Radiographs were obtained in these cases postpartum, and because none of the IUDs were identified, the diagnosis of expulsion was made. Intrauterine pregnancies complicated by IUDs are at increased risk for firstand second-trimester miscarriage, including septic abortion, and preterm delivery if the IUD is left in place Data collected from older IUD prototypes suggest a 50% miscarriage rate if the IUD is left in situ. 17,24 The removal of the IUD reduces these risks, although the process of removing the IUD carries a small risk of miscarriage itself, and the rate of miscarriage after the IUD is removed is quoted to be approximately 25%. 24,25 Subsequently the World Health Organization and Food and Drug Administration recommend that if the IUD is seen and the strings are visible or can be retrieved from the cervical os with the diagnosis of an IUP, then the IUD should be removed by gently pulling on the strings e4 American Journal of Obstetrics & Gynecology MAY 2011

5 Obstetrics Research In our series, half of the term pregnancies had successful IUD removals and one quarter had no identifiable IUDs, later diagnosed as device expulsions. Three of the 4 patients with IUDs remaining in situ suffered pregnancy losses, which is consistent with the findings of Inal et al 15 but higher than the 50% rate typically quoted. 17,24 However, the patient who suffered the 20 week demise had a fetus with a lethal syndrome that was presumed to be unrelated to the IUD. 27 Therefore, our miscarriage percentage is likely falsely elevated. Of the 13 IUDs removed, 3 (23%) suffered firsttrimester miscarriages, similar to the incidence reported in the literature. 15,24,25 Interestingly, no cases of chorioamnionitis, septic abortion, or preterm delivery between 20 and 38 weeks were documented among our patient population. With regard to symptoms, 75% of our patients with IUDs presented with complaints, and of those, 84% complained of bleeding (45%) or pain (39%). Although bleeding and pain occurred equally, 75%, or 3 of every 4 of our pregnant patients with pain, had a malpositioned IUD in comparison with only 42% of those with bleeding. However, this difference did not prove to be statistically significant. Nevertheless, from a clinical standpoint, because bleeding in the first trimester can result from implantation and other causes specific to the developing pregnancy, pain may be a more discriminating symptom with regard to IUD complications. In conclusion, we present a recent, large series of patients with serum or ultrasound evidence of pregnancy and history of IUD placement and found that more than half of the IUDs identified in the first trimester were malpositioned. FIGURE 4 IUD and ectopic pregnancy A, Coronal 3D rendering of a properly positioned copper IUD within the endometrium. No intrauterine pregnancy is visualized. B, Transvaginal image of right adnexal mass in transverse plane. An ectopic pregnancy was diagnosed in this patient. All 3 of the ectopic pregnancies in our series had properly positioned copper IUDs. IUD, intrauterine device. Moschos. IUDs in early pregnancy. Am J Obstet Gynecol MAY 2011 American Journal of Obstetrics & Gynecology 427.e5

6 Research Obstetrics TABLE Intrauterine pregnancy outcomes (n 26) Number of cases IUD status Outcome Pregnancy losses (n 6) 3 Removed All first-trimester spontaneous abortions 1 Not retrievable (no strings) First-trimester spontaneous abortion 1 Not retrievable (embedded) 17 wk preterm rupture of membranes with abortion 1 Not retrievable (no strings) 20 wk intrauterine fetal demise with lethal fetal syndrome... Term pregnancies (n 20) 10 Removed 5 No IUD seen 4 No data regarding IUD 1 IUD in placenta at delivery... IUD, intrauterine device. Not surprisingly, an IUP was 3 times as likely to be seen with a malpositioned or missing IUD. Pregnancy loss by 20 weeks occurred in a quarter of patients with intrauterine pregnancies and known outcome data. Seventy-five percent of intrauterine pregnancies resulted in term deliveries; 50% of the term pregnancies had successful IUD removals and 25% had no identifiable IUDs. Pain and bleeding occurred equally in our patient population, and although a larger percentage of patients with pain had malpositioned IUDs than those with bleeding, the difference was not statistically significant. f REFERENCES 1. Grimes DA. Intrauterine devices (IUDs). In: Hatcher RA, Trussell J, Stewart F, Cates W Jr, Stewart GK, Guest F, et al, eds. Contraceptive technology, 18th ed. New York, NY: Ardent Media; 2004: Sivin I, Stern J, Coutinho E, et al. Prolonged intrauterine contraception: a seven-year randomized study of levonorgestrel 20 mcg/day (LNg 20) and the Copper T380 Ag IUDS. Contraception 1991;44: World Health Organization. Long-term reversible contraception. Twelve years of experience with the TCu380A and TCu220C. Contraception 1997;56: Andersson K, Odlind V, Rybo G. Levonorgestrel-releasing and copper-releasing (Nova T) IUDs during five years of use: a randomized comparative trial. Contraception 1994;49: Selected practice recommendations for contraceptive use. 2nd ed. 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