Endocrine gland derived vascular endothelial growth factor (EG-VEGF) is a newly identified angiogenic and permeability-enhancing factor, predominantly expressed in steroidogenic tissues. Recently, we found that EG-VEGF is also expressed in the normal peri-implantation endometrial samples from patients of reproductive ages (80%). Immunohistochemistry analysis showed that EG-VEGF is predominantly expressed in the glandular epithelial cells and its expression is dynamic during the menstrual cycle with a peak expression at the mid- luteal phase. We also found that EG-VEGF transcripts are up-regulated in all the peri-implantation endometrial samples from the patients following the ovulating dose of human chorionic gonadotrophin in gonadotrophin-stimulated cycles and patients receiving hormone replacement therapy (HRT). In in vitro endometrial cell culture, EG-VEGF mRNA was detected in endometrial cells only in the presence of steroids, suggesting that EG-VEGF expression is highly dependent on the steroid hormones. Subsequent expression analyzes on the EG-VEGF receptors showed that hPKR-1 and hPKR-2 are differentially expressed in human endometrium, but show no significant correlation with the hormonal treatments. On the other hand, EG-VEGF transcript was rarely detected in the endometrial samples from the post-menopausal patients and patients with endometrial carcinoma. It may imply that EG-VEGF may only play a role in vascular function of peri-implantion endometrium, but is unlikely to be associated with the etiology of endometrial cancer development.