This analytical cross sectional study was approved in October 2008 to evaluate the role of endometrial dying with methyline blue during diagnostic hysteroscopy to detect new subtle histopathologies missed by the conventional hysteroscopy.100 patients were included in the study complaining of perimenopausal bleeding with no diagnosed hysteroscopic endometrial abnormalities nor a general bleeding tendency.Endometrial dying was done by instillation of 5 ml of 1% methyline blue into the endometrial cavity after diagnostic hysteroscopy. According to the pattern of methyline blue staining , 60 patients showed focal dark staining with a background of light blue stained endometrium forming group I, the remaining 40 patients showed diffuse blue staining forming group II . Group I was further subdivided into group A , B according to the age with group A (40-46 years) and group B (>46 years).The chromoendoscopy procedure led to the diagnosis of 48 more new endometrial histopathologies missed by conventional diagnostic hysteroscopy and even random endometrial curettage ., 16 cases of atrophic endometritis,29 cases of simple endometrial hyperplasia and 3 cases of atypical endometrial hyperplasia with a very significant detection value for the former and the latter hitopathologies respectively.Conclusion: Chromohysteroscopy improves the efficacy of hysteroscopy in perimenopausal bleeding and Observation of diffuse light blue staining without dark areas strongly suggests a normal endometrium free of disease.Keywords:Hysteroscopy,chromohysteroscopy, perimenopausal bleeding , atrophic endometritis, endometrial hyperplasia..