Clinical and Biochemical Characteristics of Girls with Polycystic Ovary Syndrome presenting with Amenorrhea

To evaluate the prevalence of polycystic ovary syndrome (PCOS) in girls presenting with amenorrhea and to compare the clinical and biochemical features of those with primary (PA) versus secondary amenorrhea (SA).

We performed a retrospective chart review of girls aged 12-18 years seen in the pediatric endocrine clinic for amenorrhea between 2014 and 2024. PA was defined as absent menses by age 15 or ≥3 years after puberty onset, and SA as cessation of menses for ≥6 months 1-year post-menarche. Data collected included demographics, family history, clinical features, laboratory studies, response to a progesterone challenge test and treatment. Non-parametric tests (Mann-Whitney U) and chi-square tests were used for comparisons.

Among 377 patients, 126 (33%) were diagnosed with PCOS, of whom 32 (25.4%) had PA and 94 (74.6%) had of SA. Mean age was similar in PA and SA groups (15.2 ± 1.3 vs 15.3 ± 1.5 years). BMI was elevated in both groups (37.1 ± 7.5 vs 36.3 ± 8.4 kg/m²). Family history of PCOS was more frequent in those with PA (31.3% vs 14.9%, P = .042). Failure to bleed after a progesterone challenge failure was more common in girls with PA (36.8% vs 14.0%, P = .041). Androgen levels were higher in girls with PA (P < .05).

PCOS is a frequent cause of both PA and SA in adolescents. Girls with PA exhibit greater hyperandrogenism and are more likely to fail a progesterone challenge, suggesting a more severe phenotype than in those with SA.