Dysmenorrhea

• Definition & Classification
  • Primary Dysmenorrhea: Recurrent, crampy lower abdominal pain during menstruation in the absence of pelvic pathology. Common in adolescents.
  • Secondary Dysmenorrhea: Painful menstruation due to identifiable pelvic pathology (e.g., endometriosis, adenomyosis). Common in women >25 years.
• Etiology/Pathophysiology (Primary)
  • ↑ Production of endometrial Prostaglandin F2-alpha (PGF2α).
  • Leads to potent uterine vasoconstriction, ischemia, and myometrial contractions.
  • Sensitizes peripheral pain fibers.
• Etiology (Secondary)
  • Endometriosis: Ectopic endometrial tissue; classic “dysmenorrhea + dyspareunia + dyschezia”.
  • Adenomyosis: Endometrial glands/stroma within myometrium; uniformly enlarged, soft, globular uterus.
  • Leiomyoma (Fibroids): Benign smooth muscle tumors; irregularly enlarged, firm uterus + heavy bleeding.
  • PID: Chronic inflammation/adhesions.
• Clinical Features
  • Primary:
    • Onset: Within 6–12 months of menarche (requires ovulatory cycles).
    • Timing: Starts 1–2 days before or with onset of menses; lasts 1–3 days.
    • Character: Crampy, midline lower abdominal pain; may radiate to lower back/thighs.
    • Associated Sx: Nausea, vomiting, diarrhea, headache (prostaglandin systemic effects).
    • PE: Normal pelvic exam.
  • Secondary:
    • Onset: New onset in 20s or 30s.
    • Abnormal uterine bleeding, dyspareunia, or infertility may be present.
    • PE: Abnormal findings (masses, tenderness, immobility).
• Diagnostics
  • Primary: Clinical diagnosis (history + normal exam). No labs/imaging needed initially.
  • Secondary:
    • β-hCG: R/o pregnancy/ectopic in all reproductive-age females.
    • Pelvic Ultrasound: 1st-line imaging for anatomic abnormalities.
    • Gonorrhea/Chlamydia swabs: If PID suspected.
    • Laparoscopy: Definitive Dx for endometriosis (if medical Tx fails).
• Treatment
  • Primary Dysmenorrhea:
    • NSAIDs: 1st line (Inhibit COX → ↓ Prostaglandins). Start 1–2 days prior to menses.
    • Combined OCPs: 2nd line (Induce anovulation + endometrial thinning → ↓ Prostaglandins).
    • Heat therapy, exercise.
  • Secondary Dysmenorrhea:
    • Treat underlying cause (e.g., Laparoscopy for endometriosis, Myomectomy for fibroids).