What are the Common Causes of Clotting During Menstruation?

Women may notice clotting during menstruation for a number of reasons; some of them are relatively minor and no cause for alarm, while others may be more serious and cause for a visit to the doctor. Often, clotting during menstruation is simply the result of very heavy blood flow. It may indicate an imbalance in a woman's hormones, which can be brought on by a number of things. An enlarged uterus may also be to blame. Certain medical conditions, such as fibroids, polyps, or endometriosis, may also affect the menstrual flow in such a way that clots can easily form.

When a woman's period is very heavy, clotting during menstruation can be quite common. Normally, anticoagulants released by her body during menstruation act to keep the blood from clotting, but when there is a large quantity of blood and it is leaving the body rapidly, they may not be as effective. Clots may be particularly noticeable on the heaviest days of the period.

Hormonal imbalances are another common cause of clotting during menstruation. The uterine lining may become thicker than average and form clots if estrogen and progesterone levels are shifted from normal. This may occur for a variety of reasons; some common ones include menopause, sudden weight loss, or the use of certain medications.

Women who have an enlarged uterus may also be prone to clotting during menstruation. An enlarged uterus is typically the result of stretching during pregnancy; although the uterus typically shrinks back to its original size afterward, this does not always occur and the organ is left that way permanently. Blood may tend to pool in a large uterus prior to being expelled from the body during menstruation, allowing it to clot.

Clotting during menstruation can also be the result of a number of different medical conditions. Women who have recently had a miscarriage may notice an increase in clots. Non-cancerous tumors called fibroids that form in the uterus may lead to increased buildup of the uterine lining. The flow of menstrual blood may be partially blocked by growths like benign polyps in the uterus, causing it to become backed up and allowing clots to form. Endometriosis, a condition that causes the tissue normally found in the uterine lining to form outside of the uterus, can also lead to excessive menstrual bleeding and clotting; patients who suspect they might have this issue will likely want to seek treatment from a doctor.