DEFINITION, ETIOLOGY

DEFINITION

• Amenorrhea: loss of menstrual cycle/period
• Primary: no menarche at the expected age
• Secondary: cessation of established menstruation (absence of 3 cycles or >6 months)

ETIOLOGY

Primary:

• Anatomical anomalies:
  • congenital
    • Imperforated hymen
    • Mullerian agenesis
    • Ambiguous genitalia – secondary to 5 alpha-reductase deficiency/CAH

(hypogonadotropic hypogonadism)/androgen insensitivity syndrome o       genetic

• Primary ovarian insufficiency (Turner syndrome)

• Functional hypothalamic amenorrhea (eating disorders, stress, weight loss, excessive exercise)
• PCOS (rare in primary aetiologies)
• Endocrine issues: androgen-secreting tumours, hypo/hyperthyroidism, Cushing’s

Secondary:

• Functional hypothalamic amenorrhea
• PCOS
• Premature ovarian insufficiency (hypogonadotropic hypogonadism)
• Hyperprolactinemia (pituitary tumour/iatrogenic: antipsychotic)
• Physiological: Pregnancy, Lactation, Menopause