Comparison of morphology and morphometry of preimplantation mouse uterine endometrium in natural cycle with those received superovulatory drugs, progesterone and sildenafil citrate (Viagra)

Due to relatively low implantation rate in ART, the acceleration of endometrial maturation in ART cycles is highly investigated. Progesterone has longly been used for this purpose. Since the histological characteristics are considered as a criterion for evaluation of endometrial maturation, the aim of the present study is to compare morphological and morphometrical characteristics of mice uterine endometrium, at preimplantation stage, following progesterone and Viagra treated groups. Forty adult female mice were divided into 4 groups as: control, gonadotropin, gonadotropin + progesterone and gonadotropin + Viagra. In all 3 experimental groups the mice received 7.5 I.u HMG and later HCG. Then every two female mice with one male mouse put in one cage for mating. In two groups (from 3 experimental groups) 1mg/mouse progesterone and 3mg/kg Viagra administrated in 24, 48, 72 hours interval, after HMG injection. Ninty six hours after HMG injection, the mice in 4 groups were sacrificed, and their uterine specimens were prepared for light microscopic studies. In control group the height of endometrial epithelial cells were 20.52±2.43 μm. In gonadotropin group, the heights of the cells were 20.85±2.55 μm which were not significantly different than those in control group. In gonadotropin + progesterone group the height of the cells were 17.91±2.78 μm which were significantly (P<0.05) shorter than the control and gonadotropin groups. In gonadotropin + Viagra group heights of the cells were 17.60±2.49 μm which was similar to those in progesterone group but significantly (P<0.05) shorter than control and gonadotropin groups. Ovarian hyperstimulation followed by progesterone or Viagra injection alter the morphometrical indices of luminal epithelium of endometrium, which could affect on its maturation.