Heavy Periods (Menorrhagia)
Heavy menstrual bleeding affects 1 in 3 women. Learn what defines heavy bleeding, common causes from fibroids to hormonal imbalance, and how to track your flow accurately.
Medical disclaimer
This content is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Dawn Phase is not a medical device. Always consult a qualified healthcare professional with questions about your health.
What causes it
Heavy periods can be caused by hormonal imbalances (oestrogen dominance, thyroid dysfunction), structural issues (fibroids, polyps, adenomyosis), blood clotting disorders, or be idiopathic. Anovulatory cycles — common in perimenopause and PCOS — often produce heavier bleeding because unopposed oestrogen causes the uterine lining to build up excessively before shedding. Progesterone deficiency has the same effect.
Track this symptom across your cycle
Dawn Phase logs Heavy Periods (Menorrhagia) patterns and shows you correlations — privately. No data selling.
Start free — no card neededHow to track it
Track flow using the PBAC (Pictorial Blood Assessment Chart) method: log the number of pads/tampons used, their saturation level, and the presence of clots for each day of your period. A score above 100 defines heavy menstrual bleeding clinically. Logging across multiple cycles reveals whether bleeding is consistently heavy, worsening, or variable.
When to see a doctor
See a doctor if you are soaking through a pad or tampon every hour for more than 2 hours, if you are passing clots larger than a 50p coin, if bleeding lasts more than 7 days, if you have symptoms of anaemia (fatigue, breathlessness, pallor), or if heavy bleeding is new or getting progressively worse. Heavy bleeding is treatable — it is not something to simply manage.
Related symptoms
Related conditions
Track this symptom with Dawn Phase
Log symptoms daily and see how they connect to your cycle phases.
Start tracking free →This content is for informational purposes only and is not a substitute for professional medical advice.