Pregnancy outcomes with a copper 380 mm intrauterine device in place: A retrospective cohort study in Turkey, 2011-2021.

Objectives: To investigate pregnancy outcomes in patients with pregnancies with a copper 380 mm intrauterine device (IUD) in situ at conception.

Study Design: In this retrospective study, we identified patients with pregnancies with a copper 380 mm IUD between 2011 and 2021 from the electronic health record system. According to their initial diagnosis, we classified the patients as having nonviable intrauterine pregnancies (IUPs), viable IUPs, or ectopic pregnancies. Among the viable IUPs, we divided the ongoing pregnancies into two subgroups as IUD-removed and IUD-retained. We compared the pregnancy loss (miscarriage before 22 weeks) rates and adverse pregnancy outcomes (at least one of preterm birth, preterm premature rupture of membranes, chorioamnionitis, placental abruption, or postpartum hemorrhage) of IUD-removed and IUD-retained pregnancies.

Results: We identified a total of 246 patients with pregnancies with an IUD. We excluded six (2.4%) patients without follow-up data and seven (2.8%) patients with levonorgestrel-IUD and included the remaining 233 (44 [18.9%] ectopic pregnancy, 31 [13.3%] nonviable IUP, and 158 [67.5%] viable IUP) patients. Among the 158 women with viable IUP, 21 (13.3%) underwent abortion, leaving 137 (86.7%) who elected to continue the pregnancy. A total of 54 (39.4%) patients with ongoing pregnancy had the IUD removed. We found a lower rate of pregnancy loss among those who underwent removal (18/54 [33.3%]) compared to those with a retained IUD (51/83 [61.4%], p < 0.001). After accounting for pregnancy loss, adverse pregnancy outcomes remained increased in the IUD-retained group (17/32 [53.1%]) compared to the IUD-removed group (10/36 [27.8%], p = 0.03).

Conclusions: Pregnancy in the setting of a copper 380 mm IUD is high risk. Our results demonstrate that pregnancy outcomes improve by removal of the copper 380 mm IUD.

Implications: Prior studies have suggested that the removal of the IUD improves outcomes, but all have limitations. Our results from a very large series with care in a single institution provide contemporary evidence to support copper 380 mm IUD removal to reduce the risk of both early pregnancy loss and later adverse outcomes.