Abstract
BACKGROUND: Polycystic ovary syndrome (PCOS) is one of the most common hormonal disorders that can lead to irregular menstrual cycles and hyperandrogenism. Reduced levels of progesterone and increased estrogen in these women can perpetually stimulate the endometrial tissue of the uterus. In this study, we assess the effect of PCOS induction by estradiol valerate (EV) in a rat model. MATERIALS AND METHODS: In this experimental study, adult female Wistar rats that weighed approximately 200 g were divided into control, sham, and experimental groups (n=6 per group). The experimental group received subcutaneous injections of 2 mg EV for induction of PCOS. We confirmed the presence of PCOS in the experimental group rats. Rats from all groups were subsequently killed, after which their uteri were removed and fixed for histological and cytological analyses. The uterine tissue sections were stained with hematoxylin and eosin (H&E) and iron hematoxylin (iron-H). We examined epithelium height, thickness of the uterus wall, and frequency of the mitotic cells. The data were assessed at α=0.05. RESULTS: Uterine tissue findings from the experimental group showed significant increases in the height of the uterus luminal epithelium, the thickness of the uterus wall, and the frequency of eosinophils in the endometrial stroma. We observed an increased frequency of mitotic cells in the experimental group in both luminal and glandular epithelia of the uterus. An increased rate of the glandular epithelium region was noticeable and significant. CONCLUSION: Induction of PCOS by EV could change the proliferation rate in the endo- metrial tissue of the uterus.