Polyendocrine–Metabolic Profile in Adolescents and Young Women with Ovulatory Dysfunction: A Cross-Sectional Study

(1) Background: Ovulatory dysfunction (OD) is frequently the first clinical expression of an underlying polyendocrine or metabolic disturbance. In the context of the international consensus renaming polycystic ovary syndrome (PCOS) as polyendocrine metabolic ovarian syndrome (PMOS), our primary aim was to estimate the prevalence of four OD-associated endocrinopathies—hyperandrogenemia, insulin resistance (IR), thyroid dysfunction, and hyperprolactinemia—in a Chilean symptomatic clinical cohort, and to compare their frequencies between adolescents and young adults. (2) Methods: Cross-sectional study including 251 women (≥2 years post-menarche) with confirmed OD, stratified into Group A (12–18 years; n = 96) and Group B (19–35 years; n = 155). (3) Results: Hyperandrogenemia was the most prevalent endocrinopathy in both groups (50.0% vs. 49.0%; p = 0.882), driven primarily by elevated dehydroepiandrosterone sulfate (DHEAS) in Group A (37.5% vs. 24.5%; p = 0.028). IR was significantly more frequent in adolescents (55.2% vs. 41.3%; p = 0.032). Thyroid dysfunction (primary threshold: thyroid-stimulating hormone [TSH] > 5.0 μIU/mL) was present in 2.1% and 5.2% of Groups A and B (p = 0.226). Hyperprolactinemia (>25 ng/mL; macroprolactin-excluded) was detected in 13.5% and 13.6% (p = 0.999). (4) Conclusions: All four endocrinopathies were detectable during adolescence, with prevalences largely comparable to those observed in young adult women, supporting the rationale for considering structured polyendocrine evaluation in women with OD ≥ 2 years post-menarche within the PAInT (Prolactin, Androgens, Insulin, and Thyroid hormones) framework.