By Rebecca H. Allen, MD, MPH, Editor
SYNOPSIS: In this retrospective cohort study, 233 individuals who conceived with a copper intrauterine device (IUD) in place were followed. There were 44 ectopic pregnancies, 31 non-viable intrauterine pregnancies, and 158 viable intrauterine pregnancies. Of the viable pregnancies, 137 patients continued the pregnancy and, of these, 54 had the IUD removed. Those who underwent IUD removal had a lower rate of pregnancy loss (33%) compared to those who retained the IUD (61.4%).
SOURCE: Karakus SS, Karakus R, Akalin EE, Akalin M. Pregnancy outcomes with a copper 380 mm2 intrauterine device in place: A retrospective cohort study. Contraception 2023; Jun 16:110090. doi: 10.1016/j.contraception.2023.110090. [Online ahead of print].
The authors of this study sought to better describe the outcomes of pregnancies with intrauterine devices (IUDs) in place and the benefits of IUD removal. This was a retrospective cohort study from Turkey that identified patients who conceived with a copper IUD in utero from electronic medical records from January 2011 to January 2021. Included cases had a documented pregnancy with [beta]-hCG or ultrasound and an IUD in situ confirmed on ultrasound or postpartum examination. Patients with levonorgestrel (LNG) IUDs were excluded, as well as those without follow-up information. Their clinical protocol was to remove IUDs if the strings were visible and leave the IUD in situ if no strings were visible. Clinical, obstetric, and sociodemographic data were collected, as well as adverse pregnancy outcomes, such as preterm premature rupture of membranes (PPROM), preterm birth, chorioamnionitis, placental abruption, and postpartum hemorrhage. Induced abortion was legal in Turkey prior to the 10th week of pregnancy.
The authors identified a total of 246 patients with pregnancies with an IUD in situ. Six patients with no follow-up information and seven patients with LNG-IUDs were excluded, leaving 233 patients in the sample. There were 44 (18.9%) ectopic pregnancies, 31 (13.3%) non-viable intrauterine pregnancies, and 158 (67.5%) viable intrauterine pregnancies. Of the viable pregnancies, 137 (86.7%) opted to continue the pregnancy and, of these, 54 (39.4%) had the IUD removed. The mean gestational age at the time of IUD removal was 7.4 weeks. Pregnancy loss occurred in 69 (50.4%) of the 137 women who continued their pregnancy, with 51 losses in the first trimester and 18 losses in the second trimester. Those who underwent IUD removal had a lower rate of pregnancy loss (33%) compared to those who retained the IUD (61.4%), P < 0.001. For pregnancies that continued beyond the first trimester, the mean gestational age duration was longer (35.1 weeks [± 7.2] vs. 29.8 weeks [± 9.7]; P = 0.01) in those who had their IUD removed. Adverse pregnancy outcomes, as defined earlier, were higher in the group that retained their IUD (53.1% vs. 27.8%; P = 0.03).
COMMENTARY
The IUD is a very effective contraceptive with low failure rates. The failure rate is approximately 0.2% for LNG-IUDs and 0.8% for copper IUDs.1 However, rarely, pregnancies do occur with an IUD in the uterus. Young age is a risk factor for failure because of higher rates of fertility. If they do conceive, IUD users are at higher risk of ectopic pregnancy, with a higher proportion of ectopic pregnancies occurring in LNG-IUD users compared to copper IUD users.2 Therefore, when an IUD user becomes pregnant, the first step in the clinical evaluation is to locate the pregnancy. After an ectopic pregnancy is ruled out, then a decision must be made regarding continuing an intrauterine pregnancy.
The authors of this study sought to update the data on outcomes of pregnancies with IUDs in place, since other studies on the subject are older. The data come from a single clinical center in Turkey. As such, they may not be generalizable to other institutions or countries. The data were limited only by the sample size, which, when considering pregnancies that reached viability limit, was only 32 subjects in the IUD-retained arm and 36 subjects in the IUD-removed arm. Nevertheless, with these data, we can better counsel patients on their potential outcomes.
As with older studies, the authors demonstrated that IUD removal early in pregnancy, when the strings still are visible, is the best course of action.3 This reduced the risk of pregnancy loss and adverse pregnancy outcomes overall, including PPROM, preterm birth, chorioamnionitis, placental abruption, and postpartum hemorrhage. However, the risk is not reduced to baseline even with IUD removal, and patients must be counseled on that fact.4 The authors of this study did not attempt to remove any IUDs when the strings were not visible, which usually is the standard practice.
However, there are case reports of successful IUD removal without strings visible during pregnancy using hysteroscopy or ultrasound-guided retrieval with alligator forceps, especially if the IUD is in the cervix or lower uterine segment.4 If the IUD is left in situ, the IUD then is retrieved after delivery in those instances. An ultrasound also can be used to document the IUD in the uterus.
If no IUD is seen in the uterus on ultrasound, then the device may have expelled prior to the pregnancy. A postpartum X-ray can be done to document and confirm the IUD expulsion.
For patients who desire pregnancy termination with an IUD in situ, I prefer to remove the IUD if the strings are visible at the time of pregnancy diagnosis, especially if the patient is being referred elsewhere for a termination. The patient may end up changing their mind, and it always is easier to remove the IUD with the strings visible. As the pregnancy progresses, the strings will be pulled up into the uterine cavity. Although the IUD can be retrieved during a procedural abortion with instruments or suction, the IUD must be removed prior to initiating a medication abortion. In sum, IUD removal benefits the patient when the strings are visible.
REFERENCES
- Trussell J. Contraceptive failure in the United States. Contraception 2011;83:397-404.
- Heinemann K, Reed S, Moehner S, Do Minh T. Comparative contraceptive effectiveness of levonorgestrel-releasing and copper intrauterine devices: The European Active Surveillance Study for Intrauterine Devices. Contraception 2015;91:280-283.
- Brahmi D, Steenland MW, Renner RM, et al. Pregnancy outcomes with an IUD in situ: A systematic review. Contraception 2012;85:131-139.
- Centers for Disease Control and Prevention. US selected practice recommendations for contraceptive use, 2016 (US SPR). Last reviewed March 27, 2023. https://www.cdc.gov/reproductivehealth/contraception/mmwr/spr/summary.html
