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Menstrual Clots


Um, I feel rather silly asking this, but I honestly don't know, and I can't find any information on the net giving me the answer. How do I know if what I'm experiencing is blood clotting? I only just learned of the endometrium being the uterine lining and that it actually sheds each month. I always thought it was blood clots that I'm experiencing, but now I don't know if it's that or membrane or whatever it might be called with the shedding. I don't know where to turn to find out. It's an embarrassing subject to broach, and even more so being so incredibly ignorant. If there's any chance you can help me or point me in the right direction, I'd greatly appreciate it.


That’s a very good question!

It is amazing how little solid information most of us women have about how our own bodies normally work! As a woman recently wrote, she was experiencing “the great female unknown”.

A colleague of mine from Alberta, Laura Wershler, points out that we all need to have “Body Literacy.” It’s as important as reading, writing and arithmetic!

The lining of the uterus sheds each month (called a “period”). The actual flow of a period is a mixture of discarded uterine lining cells, blood and some vaginal fluid. If flow is heavy and mostly blood, it will clump together into what is called a clot. (It is similar to blood clotting if we have a cut—very important to keep us from bleeding to death!) It is normal to have the occasional small clot on the heaviest period day. However, if a clot is bigger than a dime, it indicates that your period is too heavy. Using the daily Menstrual Cycle Diary or the Daily Perimenopause Diary flow with clots would be scored as a “4.” (If flow is really fast, then the blood doesn’t have time to clot and just comes drop, drop, dripping out in a red stream!)

Sometimes the usual period has stretchy cervical mucus mixed with it. Then the flow becomes shiny as well as red. A woman I once taught called that particular kind of menstrual flow, “currant jelly”! That period plus stretchy mucus mixture is important to pay attention to because it tells you that your estrogen levels are abnormally high during your period. And they should normally be low. Currant jelly flow is most likely to happen in perimenopausal women.

Hope this is helpful for you,
All the best,

Jerilynn C Prior MD FRCPC

Updated Date: 
Tuesday, November 19, 2013 - 13:45

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