Morphology of rabbit oviduct after microsurgical techniques for reanastomosis of the isthmus or ampulla.

Using microsurgical techniques and two layers of sutures, we reanastomosed 66 rabbit oviducts; 35 had been divided in the isthmic region and 31 in the ampullary region. With light microscopy as well as transmission and scanning electron microscopy we studied anastomosed segments and the rest of the oviducts 1 day, 1 week, and 4--12 weeks after operation. -- In the vicinity of the sutures we found slight scarring, some flattening of the mucosal epithelium with loss of differentiation and, most important, displacement of the mucosa into the muscle wall of the tube with the development of irregular diverticuli. The significance of these alterations and their possible relation to the occurrence of tubal ectopic pregnancy is discussed. We recommend that care should be taken to avoid the mucosa during total anastomosis.