OBJECTIVE: To determine the changes in endometrium and serum leptin levels during the periimplantation period of the ovum in the rat in response to exogenous ovarian stimulation by hMG and recombinant FSH (rFSH). DESIGN: Experimental animal study. SETTING: University hospital. INTERVENTION(S): A total of 100 female rats were stimulated with low and high doses of hMG (groups 1 and 2, respectively) and low and high doses of rFSH (groups 3 and 4, respectively) before mating after the regular cycle was observed. The control group of animals was not injected (group 5). The endometrium of the pregnant rats (n = 53) was analyzed by the morphometric method, and serum samples were obtained for leptin and E2 levels at baseline and on the day of implantation. The mitotic index was determined separately for endometrial surface, glandular epithelium, and endometrial stroma by light microscope. MAIN OUTCOME MEASURE(S): Morphometric analysis of endometrium, mitotic index, and serum leptin and E2 levels RESULT(S): The mean number of corpora lutea was significantly higher in groups 2 and 4. The measurement of mucosal depth was found to be significantly higher in group 4 compared with the control group (0.361 +/- 0.03 vs. 0.289 +/- 0.04). The depth of the endometrial surface epithelium was found to be significantly higher in all study groups (groups 1-4) compared with the control group. The depth of the surface epithelium was found to be significantly lower in group 1 compared with the other study groups (groups 2, 3, and 4). The depth of the surface epithelium was also significantly lower in group 2 compared with group 3 (21.58 +/- 3.56 vs. 28.21 +/- 3.56). Mitotic indices that were determined at the endometrial surface epithelium and stroma were all significantly lower in all study groups (groups 1-4) compared with the control group. There was no significant increase for the baseline leptin levels compared with the levels measured on the day of implantation. CONCLUSION(S): In an animal model, exogenous administration of gonadotropins significantly affects the morphology of the endometrium and the mitotic index in the implantation period of the embryo. These morphological effects become more pronounced as we increase the administered dose of exogenous gonadotropins. However, no differences in leptin levels were observed relative to different gonadotropin type and dose regimens.
OBJECTIVE: To determine the changes in endometrium and serum leptin levels during the periimplantation period of the ovum in the rat in response to exogenous ovarian stimulation by hMG and recombinant FSH (rFSH). DESIGN: Experimental animal study. SETTING: University hospital. INTERVENTION(S): A total of 100 female rats were stimulated with low and high doses of hMG (groups 1 and 2, respectively) and low and high doses of rFSH (groups 3 and 4, respectively) before mating after the regular cycle was observed. The control group of animals was not injected (group 5). The endometrium of the pregnant rats (n = 53) was analyzed by the morphometric method, and serum samples were obtained for leptin and E2 levels at baseline and on the day of implantation. The mitotic index was determined separately for endometrial surface, glandular epithelium, and endometrial stroma by light microscope. MAIN OUTCOME MEASURE(S): Morphometric analysis of endometrium, mitotic index, and serum leptin and E2 levels RESULT(S): The mean number of corpora lutea was significantly higher in groups 2 and 4. The measurement of mucosal depth was found to be significantly higher in group 4 compared with the control group (0.361 +/- 0.03 vs. 0.289 +/- 0.04). The depth of the endometrial surface epithelium was found to be significantly higher in all study groups (groups 1-4) compared with the control group. The depth of the surface epithelium was found to be significantly lower in group 1 compared with the other study groups (groups 2, 3, and 4). The depth of the surface epithelium was also significantly lower in group 2 compared with group 3 (21.58 +/- 3.56 vs. 28.21 +/- 3.56). Mitotic indices that were determined at the endometrial surface epithelium and stroma were all significantly lower in all study groups (groups 1-4) compared with the control group. There was no significant increase for the baseline leptin levels compared with the levels measured on the day of implantation. CONCLUSION(S): In an animal model, exogenous administration of gonadotropins significantly affects the morphology of the endometrium and the mitotic index in the implantation period of the embryo. These morphological effects become more pronounced as we increase the administered dose of exogenous gonadotropins. However, no differences in leptin levels were observed relative to different gonadotropin type and dose regimens.