Improperly placed IUDs raise chances of intrauterine pregnancy

Intrauterine pregnancy is 3 times as likely to occur when an intrauterine device (IUD) is incorrectly positioned or missing, according to a study published online February 4 in the American Journal of Obstetrics & Gynecology.

Researchers evaluated ultrasound findings, clinical symptoms, and outcomes of first-trimester pregnancies in 42 women with a history of IUD placement and a positive serum human chorionic gonadotropin test in the first trimester. Of the 36 IUDs visualized by the researchers, 15 were positioned normally and 21 were incorrectly placed.

“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,” the authors write.

Thirty-one of the women had intrauterine pregnancies. In these women, 8 IUDs were found in the endometrium, 17 were improperly positioned, and 6 weren’t visible. Indications of pregnancy included bleeding, pain, and missing strings; 11 women had no symptoms. Symptoms didn’t predict IUD malposition, the authors conclude.

Twenty of the 26 women with an intrauterine pregnancy and known pregnancy outcome delivered at term. Six pregnancies failed at 20 weeks or earlier.