Intrauterine devices in early pregnancy: findings on ultrasound and clinical outcomes

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.