Is it Normal to Have Blood Clots During Your Period?

Clots during the period can appear during the fertile stage of many women. Find out if it's normal or if you should go to the doctor.
Is it Normal to Have Blood Clots During Your Period?
María Belén del Río

Reviewed and approved by biologist and doctor María Belén del Río.

Written by Editorial Team

Last update: 15 December, 2022

Having clots during your period is something that happens to all women at some point in their life. It happens to some more often than others, but it’s quite common.

In most cases, the presence of these blood clots is normal. Although they’re annoying and unpleasant, they’re very much a part of the menstrual process. In addition, there are external factors that can influence their formation.

Why do you get clots during your period?

Clots during your period can be caused by the following factors:

1. A sudden detachment of the mucosa

During your period, the body sheds the mucosa that covers the uterus in a slow and balanced way. In cases where it comes off more quickly, clots can occur. At night, more blood usually accumulates in the vagina without being expelled and these small masses can form.

artist represenation of waiting for a period with a clock, a calender, and a red feather

2. Cysts or fibroids in the uterus


Fertile women are more likely to have intrauterine cysts or fibroids and one of the symptoms is clots during your period. Tissue grows inside the uterus, and, even though it’s mostly benign, there’s a chance it may not be. For this reason, it’s a good idea to visit a gynecologist.

3. Hormonal imbalances

Changes in certain hormones such as estrogens and progesterone are causes of clots during menstruation. These alterations occur mainly in adolescence or premenopause.

It’s important not to miss these symptoms: 6 Menstrual Irregularities You Shouldn’t Ignore

4. Anemia

These thick masses of blood can be produced by the lack of iron in the body. With the decrease of this mineral, the necessary anticoagulation loses some of its effectiveness in certain processes in the body. In these cases, it’s also necessary to carry out medical treatment.

5. A disease affecting the reproductive system

If there’s a disease that’s affecting any of the integral parts of the female reproductive system, then you can get clots during your period. It’s very likely that, in addition to this, they’ll be accompanied by severe pain in the abdominal area.

6. Miscarriage

A miscarriage in the first weeks of gestation is often mistaken for a menstruation. What many people don’t consider is the fetus and all the other fluids associated with pregnancy. Likewise, postpartum bleeding also occurs with these uncomfortable masses.

7. Eating disorders

A woman with anorexia.

Different eating disorders, such as anorexia or bulimia, have an impact on the regularity of the menstrual period. The same happens with extreme weight changes, either by increase or decrease.

Information is always a priority: Which Hormones Influence the Menstrual Cycle?

8. Stress

Anguish, anxiety states, and stress can cause a period to take longer to arrive. In this way, the bleeding that comes later is more abundant and clots of different sizes can easily form. This is a sign that your body is sending you that you should start to relax; your body is showing you the damage that can occur because of negative emotions.

When do you have to worry about clots during your period?

As we have already mentioned, in most cases, it’s very normal for clots to appear during a woman’s period. There’s nothing to worry about if it occurs every two months i.e. in alternate periods. However, there are certain factors you need to be aware of and, in these cases, we recommend that you consult a professional.

  • A constant tired feeling. A woman may have anemia without being aware of it. This is one of the causes of clots during your period, and it must be treated in time. With an iron supplement, it’s very easy to resolve.
  • Strong pain and excessive bleeding. If you notice that you have more abdominal pain, and a considerable increase in bleeding, then this could be mean there’s some underlying condition that needs to be treated.
  • The size of the clots. It’s true that it isn’t very pleasant to look at these blood clots that can occur during your period. However, you really do need to be aware of the size of these thick masses of blood, and monitor them. If the blood clots are large and form continuously, then a doctor should carry out tests.

Menstruation is a very important process in the life of women. From the first period to the last, it’s very relevant to the woman’s  fertile life. Despite the changes, annoyance, and how it affects your everyday life, it’s a vital and normal part of your life that will accompany you until you reach the menopause stage.

Being able to spend the days of menstruation calmly, treating it as a natural part of your life, will help your mood and overall health. So, knowing all the information we have given you about clots during your period will surely help you as you deal with your body’s monthly cycle.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

    • [Internet]. Cologne, Germany: Institute for Quality and Efficiency in Health Care (IQWiG); 2006-. Heavy periods: Overview. [Updated 2017 May 4]. Available from:
    • Santos, I. S., Minten, G. C., Valle, N. C., Tuerlinckx, G. C., Silva, A. B., Pereira, G. A., & Carriconde, J. F. (2011). Menstrual bleeding patterns: A community-based cross-sectional study among women aged 18-45 years in Southern Brazil. BMC women’s health, 11(1), 26.
    • Beller FK. Observations on the clotting of menstrual blood and clot formation. Am J Obstet Gynecol. 1971 Oct 15;111(4):535-46. doi: 10.1016/0002-9378(71)90470-4. PMID: 4937608.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.