Polycystic ovary syndrome: clinical presentation in normal-weight compared with overweight adolescents.

OBJECTIVE: To characterize polycystic ovary syndrome (PCOS) in adolescents and determine whether a distinct clinical presentation differentiates normal-weight (NW) from overweight (OW) PCOS.
METHODS: Retrospective chart review of patients seen in a tertiary care center from 1998-2008 who met the National Institutes of Health and/or Rotterdam criteria for PCOS (N = 211; NW = 43, OW = 168). We collected data on clinical features, biochemical markers, and ultrasound findings.
RESULTS: Patient age ranged from 11.3 to 20.3 years (mean, 15.7 ± 1.7 years), and body mass index (BMI) from 17.4 to 64.2 kg/m2 (mean, 31.7 ± 7.7 kg/m2). Seventy-one percent of patients were Caucasian, 85% had irregular menses, 69% reported hirsutism, 18% had moderate to severe acne, 91% had a high free androgen index (FAI), and 8% had abnormal thyroid-stimulating hormone (TSH) levels. The BMI-standard deviation (SD) score was 0.1 ± 0.5 in NW and 3.4 ± 1.8 in OW girls. NW girls were older at diagnosis (16.4 ± 1.4 years vs. 15.5 ± 1.7 years; P = .0006) than OW girls, less likely to have a family history of obesity (22% vs. 65%; P<.0001), and less likely to have acanthosis nigricans (11% vs. 68%; P<.0001). NW girls were more likely to have polycystic ovaries on ultrasound (88% vs. 52%; P = .01) and a lower FAI (7.3 ± 4.5 vs. 17.4 ± 12.9; P<.0001). The BMI-SD score was negatively associated with sex hormone binding globulin (r(s) = -0.52; P<.0001) and positively associated with FAI (r(s) = 0.42; P<.0001).
CONCLUSION: NW girls are more likely to be older at diagnosis and have polycystic ovaries. Other differences in presentation between groups were attributable to differences in weight. NW PCOS is likely part of a continuous spectrum of clinical PCOS rather than a distinct entity.