In most cases the Brown Vaginal Discharge is the indicator of old blood from endometrial tissues - old blood looks brown.
Brown vaginal discharge is normally just "old blood" that has been oxidized and left uterus and/or vagina late or later (not at the time of normal regular period).
During reproductive period almost all women experience brown vaginal discharge which could appear before or after period, during pregnancy, during contraception with birth control pills, during stress and/or late periods. But sometimes brown vaginal discharge could be a symptom of several hormonal dysfunctions and/or diseases and/or health conditions.
First time you can experience brown vaginal discharge during puberty - first period of female "hormonal storm". Sometimes you can have few times brown vaginal discharge before your first period and sometimes your first period could look like brown vaginal discharge. It is a temporary situation and brown vaginal discharge will disappear once you start having normal regular menstrual periods.
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