Differential Diagnosis for Foul Smelling Period Blood

• Single Most Likely Diagnosis
  • Bacterial Vaginosis (BV): This is a common condition characterized by an imbalance of vaginal flora, leading to an overgrowth of bacteria. It often presents with a foul or fishy odor, especially after menstrual periods.
• Other Likely Diagnoses
  • Trichomoniasis: A sexually transmitted infection caused by the parasite Trichomonas vaginalis, which can lead to a foul-smelling vaginal discharge.
  • Forgotten or Retained Tampon: A tampon left in the vagina for an extended period can cause a strong, unpleasant odor due to bacterial growth.
  • Vaginal Yeast Infection: Although typically associated with a "cottage cheese" discharge, some yeast infections can cause a foul odor, especially if complicated by a secondary bacterial infection.
• Do Not Miss Diagnoses
  • Toxic Shock Syndrome (TSS): A rare but life-threatening condition often associated with tampon use, characterized by fever, rash, skin peeling, and multi-organ failure. The presence of a foul odor could be an early sign.
  • Pelvic Inflammatory Disease (PID): An infection of the female reproductive organs that can cause foul-smelling discharge, among other symptoms like pelvic pain and fever.
• Rare Diagnoses
  • Foreign Body in the Vagina: Objects inserted into the vagina can cause infections and foul odors if not removed.
  • Cervical or Endometrial Cancer: Although rare, these cancers can cause abnormal vaginal bleeding and discharge with a foul odor.
  • Genital Ulcers or Lesions: Certain sexually transmitted infections (like herpes or syphilis) can cause ulcers or lesions that may become infected and emit a foul odor.