What Causes Prolonged Vaginal Bleeding While Having Bulky Uterus And Adenomyosis?

Hello, I need a clarification as since 3 months i have irregular periods with slight bleeding and a slight bulky uterus according to the Ultrasound Scan.I am 45 years ,have no children due to fibroid and adinomyosis case. I have consulted a gynecologist she suggested Tranostat tablets for 3 days which worked to stop the bleeding but after a week its the same situation, now according to the doctor she may go for D&C.Kindly let me know the reason and the step to be taken?please do clarify........thanks doctor