OBJECTIVE: Premature androgenic alopecia has been suggested as a feature of the male equivalent of the syndrome of polycystic ovary. However, the hormonal pattern of men with premature balding has been investigated in only a few studies with inconsistent results. MATERIAL AND METHODS: We examined 37 men with premature balding (defined as frontoparietal and vertex hair loss before the age of 30 years with alopecia defined as grade 3 vertex or more on the alopecia classification scale of Hamilton with Norwood modification). The plasma concentrations of total testosterone, dihydrotestosterone, epitestosterone, androstenedione, cortisol, 17-OH-progesterone (17OHP), estradiol, LH, FSH, prolactin, SHBG and TSH and free thyroxine were measured. RESULTS: The frequency of subnormal values in SHBG, FSH, testosterone and epitestosterone (but not in free androgen index) was significant in the balding men. A borderline significant trend was recorded with respect to increased levels in 17OH-P and prolactin. CONCLUSIONS: The hormonal pattern of a substantial number of men with premature balding resembles in some respects the hormonal pattern of women with polycystic ovary syndrome.