Endometrial thickening is defined as total endometrial thickness >1.4 cm during reproductive age and >0.5 cm during menopause. The thickness of the endometrium varies according to age and menstrual cycle. The thickness of the endometrium is measured with the help of ultrasonography. It is thinner in the menstrual phase, about 10 MM in the proliferative phase and up to 10-13 MM in the secretory phase. If the patient has regular menstruation, ovulation and normal menstrual flow, even if the endometrium is 15 MM in the secretory phase, it cannot be considered thickening; if the patient has long term menstrual irregularity and anovulatory type of gonorrhea, it is only meaningful to monitor the thickness of the endometrium. The vast majority of endometrial hyperplasia is a reversible lesion or remains a persistent benign state, and only a few cases may develop into cancer after a longer time interval. Ultrasound can be helpful in identifying benign and malignant endometrial lesions, but final diagnosis requires diagnostic scraping pathology.