Obstetrics and Gynaecology

Is Black Blood During Periods Normal? Causes, Charts, and When to Seek Medical Advice

admin Apr 17, 2025

Have you ever wondered, 'Why is my period blood black on the first day?' Most of the time, the period blood is red. However, one can become anxious if they notice black menstrual blood during periods. The good thing is that noticing period blood in different colors is common, ranging from bright red to brown to black. It can be harmless but occasionally indicates an underlying health issue.

Black period blood causes:

As mentioned earlier, period blood can range in various colors. Black blood during period indicates that the blood has taken a little longer to exit the uterus. When blood stays in the uterus for an extended period, oxidation occurs, leading to discoloration of the blood that commonly occurs at the start or end of the period cycle.

During the first and last days of menstruation or other periods, blood flow tends to be slow, leading to its accumulation and oxidation. However, the blackish discoloration can also occur due to various causes, such as:

Oxidation is a natural, non-concerning process that occurs when the blood has not exited the uterus immediately and is exposed to air for extended periods.
Hormonal changes alter the color and consistency of period blood. They can occur when an individual is taking hormonal birth control medications, experiencing stress, or experiencing menopause. Stopping or starting the use of birth control hormones can also alter the appearance and consistency of the menstrual blood.
Foreign body – foreign bodies left in the vagina for a long time, such as a tampon, menstrual cups, and physical birth control caps, can delay the exit of blood from the uterus leading to dark period blood.
Obstructions causing cervix narrowing can also delay blood exit from the uterus, leading to blackish discoloration of period blood.
Infections and inflammations occur due to pelvic inflammatory diseases, bacterial infections of the vagina, or sexually transmitted infections that lead to blackish discoloration of the blood.
Polyps or fibroids alter blood flow and its consistency, leading to heavy blood flow during periods and black period blood discoloration.
Missed pregnancy/miscarriage occurs in the body, which may not be known to the individual. However, any remnants of the tissues can alter the appearance of the period blood and exit as black period blood.

Black period blood signs:

Black discoloration of the menstrual blood is common during the start and end of the menstrual cycle. However, it should be observed and associated with the following signs if it occurs in the middle of the period cycle.

Severe uncontrollable pain
Foul smell
Excessive bleeding than usual.
Severe rash and itching
Fever
Dark period blood potential concerns:

Even though black period blood is common, it can also indicate potential health concerns if there are any of the following mentioned below:

Infections such as pelvic inflammatory disease and bacterial vaginosis can alter the period's blood color. Black or dark period blood color, associated with other symptoms such as foul smell, severe pelvic pain, and fever, is a matter of concern as it indicates infection. It is better to consult a healthcare professional and get thoroughly reviewed to avoid potential complications.
Polyps and fibroids in the uterus disturb the regular flow of blood, changing the color and consistency of the period blood. Uterine fibroids or polyps can cause black period blood, which is associated with black blood clots, excessive bleeding, and severe pain. Hence, it is better to consult a healthcare professional for the same.
Obstructions that block the regular flow of period blood can also cause black period blood. Cervical stenosis, surgical procedures, and severe infections can lead to the narrowing of the vagina, causing accumulation of blood and discoloration. They are a matter of concern if they are associated with pain and irregular menstrual cycles.

Black period blood consultation:

Consulting a healthcare professional is necessary if the period blood is consistently black throughout the cycle, is associated with symptoms or occurs suddenly and is associated with excessive bleeding.

Black period blood prevention:

Following a few steps helps to control black period blood. They are:

Maintaining menstrual hygiene and changing the menstrual pads, cups, or tampons regularly
Wash the private parts to avoid infections
Track the periods periodically and consult the healthcare professional for any concerns.

Black period blood is normal but can also be concerning if it is associated with symptoms. Early identification and consultation with a healthcare professional can help determine the underlying concern of black period blood.

Fortis Hospital has experienced gynecologists and obstetricians who can understand the concerns of black period blood and identify if it is associated with any underlying health issues.

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