My Daughter, 35 , Is Experiencing An Excessive Amount Of

My daughter, 35 , is experiencing an excessive amount of bleeding after her IUD came out on its own. Her doctor said there is nothing they can do to stop the bleeding but we are concerned about the amount she is loosing. How long can she expect the bleeding to go on? She did have a vaginal ultrasound done and everything looked fine. We just don't know how much is too much blood.