The color of a person's period blood can relay vital health information. For example, orange or grey blood can sometimes indicate a vaginal infection. During menstruation, the body sheds tissue and blood from the uterus through the vagina. This bloody discharge can vary from bright red to dark brown or black depending on how old it is. Blood that stays in the uterus long enough will react with oxygen (oxidize). Blood that has had time to oxidize appears darker. Hormonal changes and health conditions can also affect the color and texture of period blood.
In this article, we present a period blood chart and discuss what the different colors of period blood can mean. We also cover color changes during a period, what clots mean, and when to see a doctor.
Black blood can appear at the beginning or end of a person's period. The color is typically a sign of old blood or blood that has taken longer to leave the uterus and has had time to oxidize, first turning brown or dark red and then eventually becoming black.
Black blood can sometimes also indicate a blockage inside a person's vagina. Other symptoms of a vaginal blockage can include:
itching or swelling in or around the vagina .
Brown or dark red
Like black blood, brown or dark red is a sign of old blood, and it may appear at the beginning or end of a period. Brown or dark red blood has not had as long to oxidize as black blood and can appear in a variety of shades.
Brown blood or spotting can sometimes also be an early sign of pregnancy that doctors refer to as implantation bleeding.
Brown discharge or spotting during pregnancy can indicate a miscarriage or an ectopic pregnancy, which is when the fertilized egg implants in a fallopian tube instead of the uterus.
It is important for women who experience spotting or vaginal bleeding during pregnancy to speak to their doctor or obstetrician.