Morphological alterations of rabbit oviducts following ligature of the tubal isthmus.

An animal model of tubal sterilisation would be valuable in order to examine the problem of severe damage of the tubal wall and to study the criteria for optimal anastomosis. In a preliminary experimental group the Fallopian tubes of 30 rabbits were ligated at the isthmic segment. Specimens of the ligated portion and other tubal segments have been investigated by light microscopy and scanning and transmission electronmicroscopy one, four and twelve weeks following the ligature. Changes in the Fallopian tubes following the ligature were limited to the ligated portion. The morphological findings consisted of a flattening and decrease of differentiation of the mucous epithelium, and of a slight scarring in the tubal wall and in the subperitoneal tissue within the constricted segment. Tubal ligation at the isthmic segment provides good conditions for refertilisation, following resection of the altered portion and microsurgical anastomosis.