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What are menstrual blood clots?

Have you ever noticed thick “clots” during your period? These are menstrual blood clots, composed of coagulated blood and tissue. While they might sound concerning, they are actually completely normal for most women and individuals who menstruate. In fact, in most cases, clots indicate everything is normal.

Imagine a gummy strawberry melting in the sunlight. Or one of those chunky bits you find in a jar of jam.

They can range in color from bright red to darker hues, and normal clots are usually no larger than a penny and don’t occur frequently.

What causes menstrual blood clots?

Blood clots occur when menstrual blood (a mixture of blood, tissue, and mucus) accumulates within the uterus, awaiting contractions of the uterus to expel it from the body.

Typically, the body releases anticoagulants to thin the mixture for easier passage; however, if the body can’t do this fast enough, menstrual blood will accumulate within the uterus.

Because our blood contains tiny cells called platelets and clotting factors. When blood vessels are damaged, platelets gather at the site of injury and, together with clotting factors, form a clot to stop bleeding. During menstruation, when the uterine lining sheds, blood vessels within the uterus bleed. If blood pools in the uterus or vagina, clots form due to this mechanism.

Rest assured, it’s all very normal, especially in the first two days of menstruation when blood flow is highest.