Although the diagnostic accuracy of hysteroscopy is high, it should be considered a diagnostic technique and used together with endometrial biopsy. Hysteroscopy is useful for excluding those patients with abnormal uterine bleeding who show no signs of intrauterine pathology. The number of cases in which hysteroscopy is sufficient for reaching a diagnosis without the help of a subsequent biopsy will depend directly on the experience of the endoscopist. After a fair amount of practice, it is possible to use hysteroscopy for the identification of patients with either benign or malignant endometrial lesions with about 20% false positives and no false negatives. The combined use of hysteroscopy and biopsy leads to near 100% accuracy in the diagnosis of endometrial neoplasia and its precursors. The combination of hysteroscopy and endometrial biopsy is ideal for use in symptomatic patients for the early detection of endometrial neoplasia, its precursors, and benign lesions that cause abnormal bleeding. With benign and malignant endometrial lesions, the first symptom is generally bleeding. Zampi and coworkers analyzed the hysteroscopic finding and menometrorrhagia in 1295 women. While cystic hyperplasia and endometrial neoplasia gave rise to bleeding in many patients, many other lesions also caused the same symptom. Hysteroscopy represents the ideal technique for the examination of women over the age of 45 who complain of abnormal uterine bleeding. In association with endometrial biopsy, it can detect endometrial adenocarcinoma in its early stages and select those patients who have precursor lesions.