Ectopic pregnancies due to contralateral fistulas after sterilization by electrocoagulation; case reports.

Three cases of post-sterilization tubal pregnancy are discussed. The sterilizations were performed by bipolar electrocoagulation. The location of the pregnancy was distal to the site of sterilization. There was no continuity between the segment containing the ectopic pregnancy and the uterus. Spermatozoa reached the site of fertilization via a tuboperitoneal fistula. The existence of the fistulas was confirmed by a methylene blue test. In two cases fistulas existed on the contralateral side to the ectopic pregnancy. In the third case, bilateral fistulas were found. So, on performing a salpingectomy for ectopic pregnancy after sterilization failure, we have to be aware of contralateral fistulas. Also good understanding of the mechanism of extra-uterine pregnancy secondary to transperitoneal migration of spermatozoa is important when doing conservative tubal surgery.