Uterine cancer can also cause excessive or irregular bleeding. This is another uncommon cause of heavy periods. The womb is usually assessed with ultrasound scans and/or MRI scans. A uterine cell biopsy (Pipelle biopsy) is advised to exclude risk of malignancy in high risk cases. Hysteroscopy is usually advised to exclude abnormal uterine cells and to assess the uterine cavity for other pathology.