Add-back therapy with GnRH analogues for uterine fibroids.

Uterine fibroids (also known as leiomyomas) are the most common benign pelvic tumours among women. They may be asymptomatic, or may be associated with pelvic symptoms such as bleeding and pain. Medical treatment of this condition is limited and gonadotropin-releasing hormone (GnRH) analogues are the most effective agents. Long-term treatment with such agents, however, is restricted due to their adverse effects. The addition of other medications during treatment with GnRH analogues, a strategy known as add-back therapy, may limit these side effects. There is concern, however, that add-back therapy may also limit the efficacy of the GnRH analogues and that it may not be able to completely prevent their adverse effects.