Experiencing a menstrual period is a natural occurrence. Although the length, volume, and frequency of menstruation cycles can differ, the presence of blood clots during this time can be unsettling. 

What are menstrual clots?

When you have your period, the hormones in your body trigger the shedding of the lining of your uterus. During this shedding process, small blood vessels may bleed. In order to prevent excessive blood loss, plasma and platelets collaborate to form blood clots.

Blood clots are formed whenever a certain amount of blood remains stagnant. They are a normal occurrence to some extent, such as when you have a cut. However, with menstrual clots, if you experience significant bleeding, the blood collects inside your uterus and forms a clot as it remains there.

What is the cause of menstrual blood clots?

Menstrual blood clots are generally considered normal occurrences. They tend to appear bright red at the beginning and end of your menstrual cycle because the blood is moving quickly and does not have sufficient time to darken. During the initial days of your period when the flow is at its heaviest, you may also observe dark red or maroon clots.

There exist numerous conditions that can result in the occurrence of unusually large blood clots or a heavier menstrual flow than usual. Some of these conditions include:

• Thyroid disease
• Uterine polyps
• Uterine fibroids
• Bleeding disorders
• Uterus or cervix cancer

What leads to the formation of menstrual clots?

In individuals of reproductive age who menstruate, the shedding of the uterine lining, known as the endometrium, occurs approximately every 28 to 35 days. Throughout the menstrual cycle, the endometrium undergoes growth and thickening in response to oestrogen, a hormone found in females. Its primary function is to provide support for a fertilised egg. If pregnancy does not occur, hormonal changes trigger the shedding of the lining. This process is referred to as menstruation, commonly known as a menstrual period or period.

During the shedding phase, the endometrial tissue mixes with various substances, including blood, blood byproducts, mucus, and tissue. This combination is subsequently expelled from the uterus through the cervix, which serves as the opening of the uterus, and exits the body through the vagina.

As the lining of the uterus sheds, it collects at the bottom of the uterus, awaiting the contraction of the cervix to expel it. To facilitate the breakdown of this thickened blood and tissue, the body releases substances that prevent blood clotting, making the material thinner and easier to pass. Nevertheless, if the body's capacity to generate these substances is exceeded by the rate of blood flow, it leads to the release of menstrual clots.

Diagnosis

When diagnosing the cause of menstrual clots, your doctor will typically inquire about factors that can affect menstruation. These may include questions about past pelvic surgeries, the use of birth control, or any history of pregnancy. Your uterus will also be examined during the process.

Moreover, blood tests may be conducted by a doctor to identify hormonal imbalances. Imaging tests like MRI or ultrasound may be used to detect conditions such as fibroids, endometriosis, or other obstructions.

Treatment for menstrual clots

The primary approach to managing menstrual clots is by controlling heavy menstrual bleeding. One option is the use of hormonal contraceptives and other medications. Hormonal contraceptives work by inhibiting the growth of the uterine lining. For example, a progestin-releasing intrauterine device (IUD) has been found to reduce menstrual blood flow by up to 90 percent, while birth control pills can decrease it by approximately 50 percent. In addition to reducing bleeding, hormonal contraceptives can also help slow the growth of fibroids and other uterine adhesions.

For individuals who are unable or prefer not to use hormonal methods, an alternative medication called tranexamic acid (Cyklokapron, Lysteda) can be considered. This medication affects blood clotting and can be effective in managing menstrual clots.

Conclusion

Menstrual clots are a normal occurrence in the menstrual cycle of individuals who menstruate. Although they may appear concerning, small clots are considered common and expected. Even clots larger than a quarter in size are generally not a cause for concern unless they occur frequently. If you experience regular passage of large clots, there are several effective treatment options that a doctor may suggest to manage heavy bleeding and minimise clot formation.