Irregular menstrual cycles as defined after one year of its onset :

• Between 1-3 years of onset, if the interval between cycles is less than 21 days or more than 45 days.
• Beyond three years of onset, if the interval between cycles is less than 21 days or more than 35 days or if there are less than eight cycles in a year.
• Interval duration of more than three months for anyone cycle
• A belief that the menstrual cycle can remain irregular in adolescents and may normalize after marriage can lead to underdiagnosis or delayed diagnosis.
• It is essential to differentiate PCOS from other conditions that mimic the presentation to avoid misdiagnosis as evaluation, management and the future outcome can differ.
• Ultrasonographic criteria in adolescent girls are less defined and can be suggestive (an ovarian volume >12 ccs) but not confirmatory. These criteria considered in isolation can lead to overdiagnosis and mismanagement.

Early identification is possible in adolescent girls with periodic growth monitoring (weight, height and BMI after five years of age), use of growth charts for understanding change in BMI, and an understanding of red flag signs of BMI values, irregularities in menstrual cycles and unusual body hair patterns with or without severe acne. Lifestyle modification plays an important role besides other individually tailored treatment modalities. These adolescent girls may undergo a revisit of diagnosis at a later age, nearly eight years after the onset of menstrual cycles, to understand its implications in adulthood.