Hirsutism and oligomenorrhea are appropriate screening criteria for polycystic ovary syndrome in adolescents.

We evaluated the association of hirsutism and oligomenorrhea (persistent menstrual cycles > 45 days) as screening criteria for the detection of biochemical hyperandrogenism (BH) and polycystic ovaries (PCOM) during adolescence and determined which androgens, granulosa cell hormone, ultrasonographic parameters have the best association with polycystic ovary syndrome (PCOS). Hirsute girls with oligomenorrhea (N = 26 Hirs/Oligo group) and non-hirsute girls with regular cycles (N = 63, C group) were studied. Prevalence of BH and PCOM, diagnostic performance of androgens and ultrasound parameters for PCOS diagnosis were analyzed. BH and PCOM prevalence were higher in the Hirs/Oligo girls than in the C girls (76.9% versus 25.5%; 92.3% versus 33.3%, respectively; p < 0.0001). A complete PCOS phenotype (Hirs/Oligo with BH and PCOM) was observed in 73.1% of the Hirs/Oligo group. The presence of both BH and PCOM was observed in 7.9% of the C group. The parameters with the best diagnostic performance were free androgen index ≥6.1, testosterone ≥2.4 nmol/L, follicle number ≥12 and ovarian volume ≥10 ml anti-Müllerian hormone (AMH) exhibited a low diagnostic accuracy. Hirsutism and persistent menstrual cycle over 45 days are highly associated with BH and PCOM suggesting that the presences of both criteria are necessary for the diagnosis of PCOS during adolescence.