Amenorrhea, Primary

Key Features

• Menarche ordinarily occurs between ages 11 and 15 years (average in United States, 12.7 years)

• Primary amenorrhea is failure of any menses to appear

• Evaluate at age 14 if no menarche or breast development or if height in lowest 3% for ethnicity, or at age 16 if menarche has still not occurred

• Causes

  • Hypothalamic-pituitary (low-normal FSH)

    • Idiopathic delayed puberty

    • Pituitary tumor

    • Hypothalamic amenorrhea (eg, stress, weight change, exercise)

    • Anorexia nervosa

    • Hypothyroidism

    • Cushing syndrome

    • Gonadotropin-releasing hormone or gonadotropin deficiency

  • Hyperandrogenism (low-normal FSH)

    • Adrenal tumor or adrenal hyperplasia

    • Polycystic ovary syndrome

    • Ovarian tumor

    • Exogenous androgenic steroids

  • Uterine causes (normal FSH)

    • Absence of uterus

    • Imperforate hymen

  • Ovarian causes (high FSH)

    • Turner syndrome

    • Autoimmune ovarian failure

  • Pseudohermaphroditism

    • Complete androgen insensitivity syndrome: individuals are born with completely normal external female genitalia, although some may have labial or inguinal swellings due to cryptorchid testes

    • Partial androgen insensitivity syndrome: individuals have variable degrees of ambiguous genitalia

  • Pregnancy (high human chorionic gonadotropin)

Clinical Findings

• Nausea, breast engorgement suggest pregnancy

• Headaches or visual field abnormalities suggest hypothalamic or pituitary tumor

• Obesity and short stature suggest Cushing syndrome

• Hirsutism and virilization suggest excessive testosterone

• Short stature suggests growth hormone or thyroid hormone deficiency

• Short stature and gonadal dysgenesis indicate Turner syndrome

• Tall stature suggests eunuchoidism or acromegaly

• Anosmia suggests Kallmann syndrome

• Perform pelvic and rectal examination to assess for hymen patency and presence of a uterus

Diagnosis

• Serum FSH, LH, prolactin (PRL), testosterone, TSH, free T₄, and pregnancy test

• Serum electrolytes

• Further hormone evaluation if patient is virilized or hypertensive

• MRI of hypothalamus and pituitary is used to evaluate teens with primary amenorrhea and low or normal FSH and LH—especially those with high PRL levels

• Pelvic duplex/color sonography is very useful

• Karyotyping

Treatment

• Treatment directed at underlying cause

• Hormone replacement therapy for females with permanent hypogonadism

• See Amenorrhea, Secondary & Menopause