The color of vaginal blood is usually expected to be a bright to dark redĀ  and a brown vaginal bleed may be concerning since it is not the norm. Brown vaginal blood, either light or dark in color, usually indicates that the blood is not fresh and has been contained in the vagina or uterus for a period of time before being expelled. It is important to identify any vaginal secretion because brown vaginal discharge is often mistaken for brown vaginal bleeding.

Causes of Brown Vaginal Blood

Brown vaginal secretions may at times be a vaginal discharge streaked with ‘old blood’ – blood that is breaking down and has taken a period of time before it exits through the vagina. At other times, a brown vaginal discharge may occur on its own with no signs of bleeding and this may seen in vaginal infections or pelvic inflammatory disease. Any of the causes of abnormal vaginal bleeding may appear as brown vaginal blood if the bleeding occurs slowly thereby allowing the blood to degrade over time. Some of the causes of brown vaginal bleeding include :

  • Retained menses. The sloughing of the inner wall of the uterus (endometrium) is usually expelled during menstruationĀ  but at times a small portion of the uterine contents may be retained. If expelled after a couple of days or more, it may appear as brown vaginal bleeding. In the case of retained menses, this is usually a small amount that may occur a few days after you finish your period.
  • Induced abortion. Using the abortion pill or having an illegal abortion may result in some of the uterine contents being expelled for days and weeks after the abortion. This may appear as brown vaginal bleeding with clots that are dark brown to black in color. In legal abortions, a D&C (dilation and curettage) is conducted and due to manual aspiration, most, if not all of the uterine contents are removed at the time of the abortion. This makes any late brown vaginal bleeding less likely.
  • Miscarriage. Depending on the stage of your pregnancy when you miscarried, remnants of the fetus, placenta or parts of the inner lining of the uterus (endometrium) may be expelled over days or even weeks after the incident. It is important for women who have miscarried to consult with their doctor and verify if a D&C (dilation and curettage) is necessary.
  • Infections of the vagina, uterus or fallopian tubes may cause slight bleeding that degrades before it exits the vagina. If it is a slight bleed and the infection is limited, a brown vaginal bleed may be noticed for a short period of time. Other symptoms like pain and a fever may also be present. Sexually transmitted diseases (STD’s) may also be responsible for brown vaginal bleeding with/without a discharge and this may occur over a long period of time.
  • Cancer, especially in cases of cervical cancer where there is slight bleeding and ulceration of the cervix, a brown vaginal bleed may be noticed occasionally. In this case, the abnormal vaginal bleeding may occur over a duration of time and increase in severity at the malignancy progresses.

Article reviewed by Dr. Greg. Last updated on March 28, 2012