Amenorrhea

Basics

Description

Absence of menstruation
Primary amenorrhea:
- No spontaneous uterine bleeding by age 16 yr or within 5 yr of breast development, which should occur by age 13
Secondary amenorrhea:
- Absence of uterine bleeding for 3 mo in a woman with prior regular menses or for 9 mo in a woman with prior oligomenorrhea
- More common than primary amenorrhea
- Pregnancy is the most common cause

Etiology

Primary:
- Gonadal failure
- Hypothalamic–pituitary disorder
- Chromosomal abnormalities
- Imperforate hymen
- Gonadal dysgenesis (e.g., Turner syndrome)
Secondary:
- Pregnancy, breastfeeding, postpartum state
- Intrauterine adhesions (Asherman syndrome)
- Hypothalamic–pituitary–ovarian axis dysfunction
- Polycystic ovarian syndrome (PCOS)
- Endocrinopathies
- Obesity, starvation, anorexia nervosa, or intense exercise
- Drugs:
  - Oral contraceptives
  - Antipsychotics
  - Antidepressants
  - Calcium channel blockers
  - Chemotherapeutic agents
  - Digitalis
  - Marijuana
- Autoimmune disorders
- Premature ovarian failure
- Menopause

Diagnosis

Signs and Symptoms

History

Menarche and menstrual history
Sexual activity
Exercise, weight loss
Chronic illness
Medications
Previous CNS radiation or chemotherapy
Family history
Infertility
Contraception use
Galactorrhea:
- Pituitary tumor
Hirsutism/acne:
- PCOS
- Cushing syndrome
- Hyperandreogenism
Illicit drug use:
- Effect on prolactin
Headaches or vision changes:
- CNS tumor
Temperature intolerance, palpitations, skin changes, diarrhea, tremor
- Thyroid

Physical Exam

Low estrogen:
- Atrophic vaginal mucosa
- Mood swings, irritability
High androgen:
- Truncal obesity
- Hirsutism
- Acne
- Male-pattern baldness
Thyroid exam
Pelvic/genital exam
Tanner staging

Essential Workup

Urine pregnancy test (UPT)

Diagnostic Tests and Interpretation

Lab

If pregnancy test is negative, no further testing is needed emergently
May send TSH, LH, FSH, and prolactin for follow-up by gynecology or primary care physician

Imaging
None needed emergently unless concern for ectopic pregnancy or other emergency as directed by patient's presentation

Diagnostic Procedures/Other
None needed emergently

Differential Diagnosis

Pregnancy
Mullerian agenesis:
- Congenital malformation of the genital tract
- Normal breast development without menarche
- Associated with:
  - Fused vertebrae
  - Urinary tract defects
Transverse vaginal septum
Imperforate hymen
Complete androgen insensitivity syndrome
Asherman syndrome:
- Intrauterine synechiae
- Due to gynecologic instrumentation
Primary ovarian insufficiency
Hypothalamic/Pituitary
Prior CNS infection, trauma, or autoimmune destruction of pituitary
Polycystic ovary syndrome
Contraceptive use
Thyroid disease:
- Hyperthyroid more likely than hypothyroid
Adrenal disease

Treatment

Pre Hospital

If amenorrhea is the result of pregnancy, stabilize patient as appropriate for pregnancy

Ed Treatment/Procedures

Reassurance and referral for follow-up

Medication

Defer for gynecology evaluation

Ongoing Care

Disposition

Admission Criteria
Admit if ectopic pregnancy cannot be ruled out

Discharge Criteria
Discharge with appropriate referral

Issues for Referral
Referral to gynecology

Follow-Up Recommendations

Gynecology follow-up is recommended

Pearls and Pitfalls

Pregnancy is the most relevant etiology of amenorrhea in the emergency department:
- UPT may give false negative with low urine specific gravity
- UPT sensitivity for β-hCG level may vary depending on type/manufacturer
- High concern for amenorrhea due to pregnancy, specifically an ectopic, may warrant a qualitative serum pregnancy test
Anorexia nervosa is an important consideration in patients with amenorrhea, particularly in adolescents
Hyperprolactinemia from use of antipsychotic drugs is a common etiology of amenorrhea in psychiatric patients

Additional Reading

Heiman DL. Amenorrhea. Prim Care Clin Office Pract. 2009;36:1–17.
Klein DA, Poth MA. Amenorrhea: an approach to diagnosis and management. Am Fam Physician. 2013;87:781–788.
Lentz G, Lobo R, Gershenson D, et al. Comprehensive Gynecology, 6th ed. Philadelphia, PA: Mosby; 2012.
Patrice Committee of the American Society for Reproductive Medicine. Current evaluation of amenorrhea. Fertil Steril. 2006;86:S148.
Rosenberg HK. Sonography of the pelvis in patients with primary amenorrhea. Endocrinol Metab Clin N Am. 2009;38:739–760.
Santoro N. Update in hyper- and hypogonadotropic amenorrhea. J Clin Endocrinol Metab. 2011;96:3281–3288 [PMID:22058375].