Algorithm of Transvaginal Ultrasound and/or Hysterosalpingogram for Confirmation Testing at 3 Months after Essure...

To evaluate the algorithm of transvaginal ultrasound (TVU) and/or modified hysterosalpingogram (HSG) confirmation testing 3 months after Essure placement to determine if women can rely on the device for permanent birth control.

Interim analysis of an ongoing 10-year, prospective, multicenter, nonrandomized, single-arm, international trial (Canadian Task Force classification II-2).

Twenty study centers in the United States (n = 12), Canada (n = 1), The Netherlands (n = 6), and Spain (n = 1).

Women undergoing the Essure procedure for permanent birth control.

Based on the algorithm for confirmation testing, women with an uncomplicated Essure procedure underwent TVU as the confirmation test; modified HSG was used for women ineligible for TVU, when TVU findings were abnormal or inconclusive, or based on the physician's discretion.

Co-primary endpoints (intention-to-treat [ITT] population) were the reliance rate and the 1-year pregnancy rate. Safety evaluation was based on adverse events. Bilateral insert placement was attempted in 597 women (ITT population) and achieved in 582 of 597 (97.5%). A total of 547 women were told to rely on Essure for permanent birth control. Both co-primary endpoints met prespecified limits: based on Bayesian statistics, the reliance rate was 91.6% (547/597; 95% credible interval, 89.2%-93.6%) and the 1-year pregnancy rate .67% (95% credible interval, .16%-1.53%). Using the algorithm for confirmation testing, of 547 subjects told to rely on Essure, 470 (86%) underwent TVU alone, 30 (6%) had modified HSG alone, and 47 (9%) had TVU followed by modified HSG. Four women became pregnant after being told to rely on Essure. They all had confirmation testing with TVU alone, and each initially read incorrectly as optimal insert locations. In each case postpregnancy follow-up and root cause analysis revealed unsatisfactory insert locations, 2 of which were perforations. Most adverse events were mild and unrelated to Essure.

The algorithm of TVU and/or modified HSG confirmation testing 3 months after Essure placement can determine that a woman can rely on the device for permanent birth control. The adverse events observed are consistent with the known safety profile of Essure. (clinicaltrials.gov: NCT01327105.).