On average, 10 in 100 women have heavy menstrual bleeding, which is more than 80ml of blood in the entire menstrual cycle. 80ml equals 1/3rd of a cup or more than 5 tablespoons.
Flooding = Leaking through despite using a tampon or pad
Clots = Clumps of blood and lining tissue
The average menstrual cycle is 21-35 days with bleeding over 3-7 days usually, and in some cases up to 10 days.
Causes of Heavy Menstrual Bleeding
Blood Disorders
In younger women, von Willebrand Factor deficiency (clotting factor), low platelets (thrombocytopenia), and bleeding disorders like haemophilia can cause heavy menstrual bleeding. However, these conditions will also cause the likelihood of increased bleeding from anywhere, with examples being nosebleeds, bleeding gums and easy bruising.
Structural Causes
Fibroids (benign growths) in the uterus, polyps (growths of the lining of the uterus), adenomyosis (extension of growths into the muscular layer of the uterus), and endometrial hyperplasia (abnormal thickening of the lining of the uterus) are all causes of heavy bleeding with varying intensity of pain.
Endometriosis (presence of uterine lining tissue outside of the uterus that bleeds with the menstrual cycle) is another significant cause of heavy bleeding and pain.
Why Investigation is Important
Heavy bleeding requires investigation with appropriate management as it can cause iron deficiency with or without anaemia. Some conditions could be precancerous, such as polyps and endometrial hyperplasia.
Hormonal Conditions
Polycystic Ovarian Syndrome (PCOS)
Polycystic ovarian syndrome (PCOS) consists of a number of symptoms and signs including heavy, light, infrequent or frequent bleeding. DHEA-S (dehydroepiandrosterone sulphate) can be elevated in PCOS, being an androgen, sometimes along with testosterone and the Free Androgen Index (FAI). Checking prolactin is also useful, as increased levels can lead to absence of periods.
Thyroid Disorders
Thyroid over- and under-activity can cause irregularities in the menstrual cycles, sometimes causing them to skip for months. These conditions can cause delayed puberty, can impact fertility, cause miscarriages, and affect the menstrual flow.
The Role of Vitamin D
Vitamin D behaves like a hormone in many systems, impacting our sleep, menstrual cycles, mood, structure of bones, muscles and teeth, along with many functions of our gut.
