On the basis that gonadotrophin-releasing hormone agonists (GnRHa) induce a significant but transient shrinkage of leiomyomas and that oral contraceptive use may be associated with a decreased risk of fibroids, we tested the hypothesis that sequential GnRHa/low-dose oral contraceptive treatment could be a therapeutic alternative in perimenopausal women with uterine fibroids. Six premenopausal women with leiomyomata uteri were treated with D-tryptophan-6-luteinizing hormone-releasing hormone (D-Trp-6-LHRH) depot (Decapeptyl 3.75) for 6 months and demonstrated a significant reduction in mean uterine volume. A low-dose oral contraceptive containing 30 micrograms of ethinyl oestradiol plus 150 micrograms of desogestrel was given during the ensuing 12 months. When GnRHa therapy was discontinued, there was a rapid regrowth of the uterine fibroids and the uterine volume had reached, or even exceeded, pretreatment values by the eighth to 12th month of contraceptive therapy. Sequential GnRHa/low-dose oral contraceptive treatment is not a useful tool for leiomyomata uteri.