Dysmenorrhea

Primary Dysmenorrhea is painful menses due to excess prostaglandin production by the endometrium → uterine contractions and ischemia. There is no identifiable pelvic pathology. Typically begins 6–12 months after menarche (after ovulatory cycles start)

Clinical Presentation

• Crampy lower abdominal pain that starts 1–2 days before menstruation
• Peaks on the first day of bleeding
• May radiate to back or thighs
• Associated symptoms:
  • Nausea, vomiting
  • Diarrhea
  • Fatigue, headache

Diagnosis

• Clinical diagnosis - based on history
• Normal pelvic exam
• If symptoms are severe, atypical, or refractory to treatment → consider secondary causes (e.g. endometriosis, adenomyosis)

Treatment

• First-line
  • NSAIDs (e.g. ibuprofen, naproxen)
    • Start 1–2 days before menses or at onset of pain
    • Inhibits prostaglandin synthesis
• Second-line
  • Hormonal contraceptives (OCPs, patch, ring)
    • Suppress ovulation and reduce endometrial prostaglandins

Teenage girl with cyclic lower abdominal pain starting before her period, improving with NSAIDs or OCPs, normal pelvic exam → primary dysmenorrhea

Non-responders:

• Evaluate for secondary dysmenorrhea
  • Pelvic ultrasound if exam or history suggests another cause