Does the shape of the copper intrauterine device play a role in expulsion? Results from the ongoing European Active Surveillance Study on LCS12.

OBJECTIVE: To compare the incidence of expulsion for different copper intrauterine device (IUD) shapes.

STUDY DESIGN: We conducted a secondary analysis of the ongoing, prospective, non-interventional European Active Surveillance Study on LCS12 (EURAS-LCS12). Users of newly inserted IUDs were recruited in 10 European countries via a network of approximately 1,200 clinicians. We restricted the analysis to copper IUD users. In the main analysis, we classified copper IUDs by shape [Nova-T frame, Tatum-T frame, Multiload frame, frameless IUDs and intrauterine balls], without differentiation of size. We calculated the cumulative incidence, crude, and adjusted hazard ratios for expulsion. Covariates included in the adjusted analyses were age, BMI, parity, education, income, IUD user status, marital status, length of device, heavy menstrual bleeding, and clinician's experience.

RESULTS: We included 26,381 copper IUD users from the EURAS-LCS12 dataset for this study. The most frequently used IUD shape was the Nova-T frame (14,724 [55.8%]) followed by the Tatum-T frame (4,276 [16.2%]), frameless IUDs (3,374 [12.8%]), Multiload frame (2,962 [11.2%]), and intrauterine balls (IUBs) (1,045 [4.0%]). Cox regression analysis regarding expulsions yielded an adjusted hazard ratio of 0.8 (95% CI, 0.7-1.0), 1.3 (95% CI, 1.0-1.8), 1.6 (95% CI, 1.2-2.1) and 3.6 (95% CI, 2.7-4.9) for Nova-T frame IUD, frameless IUDs, Multiload frame IUDs and IUBs versus Tatum-T frame IUD, respectively.

CONCLUSION: The risk of expulsion following placement of a copper IUD is related to IUD shape, with Nova-T frame and Tatum-T frame IUDs demonstrating the lowest risk.

IMPLICATIONS: Our finding of a higher risk of expulsion observed with Multiload frame, frameless, and intrauterine ball copper IUDs compared to Tatum-T frame and Nova-T frame devices during real world use has clinical importance. Clinicians may choose to use these data when counseling patients.