The purpose of endometrial ablation is to lessen or stop menstrual flow. There must be no plans to conceive afterwards as this procedure is essentially sterilizing – but must not be regarded as contraceptive in itself. For this reason the procedure is often combined with tubal ligation. A 5 mm diameter rod-lens telescope with a channel for instruments, attached to a video camera is passed through the cervix (or mouth of the womb). Occasionally a laparoscopy is required at the same time. The roller ball device is attached to a diathermy current (electricity) which burns away the lining of the uterus (endometrium).