Brown & Red Period Blood: What the Colors Mean

Menstrual blood color changes reflect oxidation time and flow rate, not necessarily pathology.

Normal Variations

• Bright red: Fresh, rapid flow (early days).
• Dark red/brown: Older blood, slower flow (start/end of period); hemoglobin oxidized to methemoglobin.
• Black: Very old blood (end of period).

Potential Concerns

• Brown spotting mid-cycle: Ovulation bleeding, implantation (if pregnant), hormonal fluctuation, polyp/fibroid.
• Persistent brown discharge + odor/pain: Infection (BV, trichomonas, PID), retained tampon.
• Brown bleeding in pregnancy: Threatened miscarriage, ectopic, cervical irritation – needs urgent eval.

When to See a Clinician

• New pattern change persisting >3 cycles
• Postmenopausal bleeding
• Pregnancy + any bleeding
• Associated pain, fever, malodor, heavy flow