This study is designed to evaluate the effectiveness, safety and tolerability of a low dose of purified FSH administration using a fixed protocol in oligomenorrheic patients not desiring pregnancy. We used a low dose (75 IU/day for 5 days) of purified FSH (Metrodin®) in 10 oligomenorrheic patients (aged 18–30) for 25 cycles. The onset of menstruation occurred in 7 patients (70%) and in 19 treatment cycles (76%), the ovulation was verified in 5 of these patients (50%) for 13 cycles (52%). One patient had spotting after the treatment, 2 patients did not have any response. The treatment did not cause side effects and it showed a good tolerability.