Endometrium procurement and transplantation restores fertility in rats

Abstract

Research questionCan rat endometrium be successfully procured and transplanted, and can a similar method be used to procure human endometrium? DesignRat endometrium was procured using an endometrium stripping method and transplanted into female Sprague–Dawley rats. Macroscopic and histological changes, endometrial receptivity-related protein concentrations and fertility were assessed. Additionally, a preliminary experiment was conducted to procure human endometrium using a similar method. ResultsEndometrium was successfully procured from both rats and humans, which contained intact endometrium and parts of the adjacent inner annulus myometrium. Endometrium auto-transplantation was conducted in rats and the procedure lasted a total of 41.3 ± 5.7 min with a mean blood loss of 0.09 ± 0.04 g. The transplanted endometrium survived well, but a fibrotic zone formed between the transplant and recipient tissue. Compared with sham rats, those with endometrium transplantation had similar endometrial thickness and endometrial gland numbers but reduced vascular density at 8 weeks after surgery. Endometrium transplantation also retained expression of the endometrial receptivity-related proteins leukaemia inhibitory factor and vascular endothelial growth factor. In contrast to non-pregnancy in the stripped horn, a mean of 5.0 ± 2.7 fetuses developed in the transplanted horn, and full-term live fetuses were conceived in the horns with transplanted endometrium. ConclusionsEndometrium procurement by stripping method can obtain an intact and functional endometrium, and endometrium transplantation can reconstruct the uterine cavity and restore fertility in rats.