See GYN... Depends upon what is causing the bleeding; "normal" menses cycle; or dysfunctional uterine bleeding? Hard to comment without knowing at least your age (which women do not like to reveal :) and without having examined you. Better for you to have your existing gyn examine you and then take it from there.
Which IUD? Suspect mirena (levonorgestrel). If so and less than six months into it, stick with it. Beats unwanted pregnancy and will almost always resolve. Your md can give you some extra estrogen as well.