Add-back therapy for long-term use in dysfunctional uterine bleeding and uterine fibroids.

The gonadotrophin-releasing hormone (GnRH) agonists are an efficacious medical approach for the management of both dysfunctional uterine bleeding (DUB) and uterine fibroids. However, due to the long-term effects of GnRH agonists on bone mass, their use is restricted to short courses. Add-back hormone replacement therapy (HRT) is one strategy that could minimise the hypo-oestrogenic effects of GnRH agonists, without nullifying their therapeutic effects. In one study of add-back therapy with cyclical oestradiol/norgestrol in combination with Zoladex (goserelin acetate) in women with subjective DUB, the duration of menstruation, the number of days of heavy bleeding and objective blood loss were all significantly (P < 0.001) reduced. There was also significant (P < 0.001) symptomatic improvement. Furthermore, in 51 patients with symptomatic uterine fibroids, combined oestrogen/progestogen given for 21 months after initial GnRH agonist treatment for 3 months did not promote fibroid regrowth. In contrast, in women randomised to progestogen only, there was a gradual increase in uterine volume. The combination of GnRH agonists and add-back HRT appears beneficial for women with either DUB or fibroids.