You are here

Heavy flow


Heavy flow means losing more menstrual blood than is normal. A normal menstrual period requires us to change two soaked normal-sized sanitary products (vaginal pads, tampons) two to four days a cycle or to empty a menstrual cup of a teaspoon (5 millilitres, ml) of blood twice a day for two to four days in a period. Normal cycles last from three to six days; heavy flow usually, but not always, lasts longer than seven days. Women often describe heavy flow as "flooding," or "clotting" and requiring that they change sanitary products every couple of hours during the day.

The official definition of heavy flow is loss of 80 ml or more blood in one menstrual period since that amount of blood loss causes iron-loss anemia in 80 of 100 women. Since 5 ml is a teaspoon and a soaked usual-sized tampon/pad holds about that much, heavy flow means losing 16 teaspoons or soaking 16 normal-sized pads/tampons (or emptying a full 30-ml menstrual cup almost three times) in one whole period.

Heavy flow is usually caused by too much estrogen (that makes the lining of the uterus grow very thick and fragile) and too little progesterone (whose job is to control endometrial growth and make it stronger). Heavy flow is most common in the teen years and in perimenopause when it is experienced by at least 25 of every 100 women. The good news is that simply taking one tablet of ibuprofen (over the counter, non-steroidal anti-inflammatory) (200 mg is the usual-sized tablet) with each meal will decrease heavy flow by a quarter to a half. Tell every woman you know! Read more about heavy menstrual flow here.

Estrogen’s Storm Season: Stories of Perimenopause

Estrogen's Storm Season

by Dr. Jerilynn C Prior

New second edition available

Estrogen’s Storm Season is now available in BOTH print and eBook (Mobi and ePUB) versions!

All royalties are recieved in our Endowment fund (overseen by UBC) and support CeMCOR's research and future.

It is full of lively, realistic stories with which women can relate and evidence-based, empowering perimenopause information. It was a finalist in 2006 for the Independent Publisher Book Award in Health.

Purchase your ebook copy via our Amazon Kindle or
Google Play storefronts!

Paperback copies (with updated insert) still available here.

Join a Study:

Get Involved

Volunteer research participants are the heart of all CeMCOR research. Participants are invited to provide feedback on study processes, to learn their own results and at the end of a study, be the first to hear what the whole study found. Please become a CeMCOR research participant—you can contribute to improving the scientific information available for daughters, friends and the wider world of women.