Primary oligomenorrhea

This code describes abnormally infrequent or light menstrual periods from the onset of menstruation, without a prior history of regular cycles. It indicates a primary menstrual disorder characterized by prolonged intervals between menses (typically greater than 35 days) or very scanty flow.

Apply this code when documentation specifies a patient has experienced infrequent or light menstrual periods since menarche. This diagnosis is supported by a patient history detailing consistently long cycles or minimal bleeding from the beginning of their reproductive years, without an intervening period of normal menstruation.

• Differentiate from secondary oligomenorrhea, which occurs after a period of normal menstrual cycles.
• Ensure documentation clearly states "primary" to support this specific code.
• Consider co-reporting codes for underlying causes if identified, such as endocrine disorders (e.g., polycystic ovarian syndrome).