Endometrium is the inner layer of the uterus. Normally the thickness of the endometrium starts increasing after the menstruation starts from 4mm and reaches upto 10 mm. every month a woman gets her menstrual cycle and this inner layer is shed, called as menstruation. The importance of the thickness of this endometrium or the inner layer of the uterus is in all the age groups. In the younger age group if there is too much of thickness and she bleeds heavily, she has got abnormal uterine bleeding, but after the age of 45 if she has heavy bleeding and the inner layer is very thick, we sometimes recommend curetting and subjecting the layer to pathology testing to rule out hormonal changes or hyperplasia, which is a precancerous condition if we have to consider a post menopausal woman who has stopped menstruating, then the importance of endometrial thickness is like this. If the endometrial thickness is less than 4mm, this patient is very unlikely to have cancer of the endometrium in future. If the thickness is above 6mm, we keep her under observation if the patient has an endometrial thickness of more than 10mm, we have to subject this patient to D & C and further histopathological examination to rule out whether she has hyperplasia, that is a precancerous condition or whether she is already going towards malignancy and developing cancer.