Experimental model of heterotopic uterus transplantation in the laboratory rat.

The present study describes a standardized experimental model of whole-uterus-and-ovaries heterotopic allotransplantation in the laboratory rat. Fifteen transplantation procedures were done. The anatomy of the pelvic region was studied with an additional 20 dissections, noting the topographical and vascular anatomy of the uterus, fallopian tubes, and ovarian vessels. Recipients were randomized into three groups. The average operative time was 150 min. The postoperative survival rate was 100%. Postoperative vascular anastomosis patency was 100%, and 26% at 72 hr. Recipients were euthanized at 24 hr (group I), 48 hr (group II), and 72 hr (group III); grafts were harvested and examined macroscopically, and fixed in formaline for histopathological and immunocytochemical analysis. Failure in 74% of the grafts at 72 hr was due to early thrombosis, starting from the capillary bed and progressing towards the main feeding pedicles. More studies must be undertaken to further understand the rejection mechanisms in transplanted reproductive organs. The efficiency, feasibility, and safety for such an operation in humans remain to be proven. We consider the present model a suitable tool to study all the above-mentioned goals.