Sterilization failures with bipolar tubal cautery.

From a consecutive series of 105 patients undergoing bipolar tubal sterilization (BPS), ten pregnancies were reported, and a tubal patency rate of 16% was found at hysterosalpingography. There were no significant clinical variables separating the BPS failure patients from those with successful sterilization. Ninety percent of the BPS failures were intrauterine, and 90% occurred within three cycles of BPS. The results of this investigation suggest that (1) BPS tubal occlusion may be associated with an increased failure (pregnancy and tubal patency) rate; (2) the majority of BPS failures are intrauterine gestations; (3) delayed fibrosis, rather than immediate tubal destruction, may be the mechanism of BPS tubal occlusion; (4) for maximum effectiveness, patients undergoing BPS should use alternative contraception for two to three cycles; and (5) surgeons employing BPS require precise training in the application of this modality of female sterilization.