Diagnosing PMOS in adolescents: Criteria, ultrasound limits, and red flags

Cree opens by clarifying that the PMOS name change did not alter diagnostic criteria. Three criteria define the syndrome: irregular menses, clinical or biochemical signs of elevated androgens, and — in adults only — ovarian findings by ultrasound or, when imaging isn't available, anti-Müllerian hormone. For adolescents less than two years post-menarche, irregular cycles mean fewer than 21 or more than 45 days between periods, or any single gap beyond 90 days; adults use a tighter 21-to-35-day window. Because ovarian criteria don't apply until eight years post-menarche, Cree explains, adolescents must show both irregular menses and hyperandrogenism — a single criterion places a teen only in an "at risk" category. Appelbaum adds that transvaginal ultrasound often isn't feasible in adolescents who aren't sexually active, transabdominal imaging can't reliably measure ovarian volume or antral follicle count, and normal values for adolescent ovaries remain poorly defined — reasons the field leans on clinical judgment rather than imaging at this age.