Why visual volume is unreliable
Menstrual fluid includes blood, shed lining, and other secretions, so appearance does not translate directly into millilitres of blood loss. Home visual estimates are therefore imprecise.
Practical observations are more useful: how often products are changed, whether protection must be doubled, whether sleep or normal activities are disrupted, how long bleeding lasts, the approximate size of clots, and whether fatigue, dizziness, or breathlessness occurs.
Signs of heavy menstrual bleeding
ACOG, the CDC, and Mayo Clinic list similar signs: soaking a pad or tampon every hour for several hours, changing more often than every two hours, using double protection, waking to change, bleeding longer than seven days, or passing clots around 2.5 cm or larger.
Repeated patterns matter, but do not wait for repetition when bleeding is extreme. ACOG advises emergency evaluation when hourly soaking continues for more than two hours and chest pain, shortness of breath, lightheadedness, or dizziness is also present.
What can make a period heavier
Plenty of things can raise the volume, and Mayo Clinic is upfront that sometimes no cause is found at all. Hormone shifts are a common thread, including thyroid problems and PCOS. So are cycles where no egg is released, which happen most in the first year after periods begin and again around perimenopause, because without ovulation the lining can build up and shed heavily.
Structural causes include fibroids, polyps, and adenomyosis. A copper IUD can make periods heavier, especially in the first year. Blood thinners can too. And inherited bleeding disorders such as von Willebrand disease are a known cause that often goes unrecognised. This is a map of the territory, not a checklist for diagnosing yourself, which is a job for a clinician with your history in front of them.
When is it worth seeing a clinician?
Some thresholds are clear enough to act on. Mayo Clinic says to seek help before your next scheduled exam if bleeding soaks at least one pad or tampon an hour for more than two hours in a row, if you bleed between periods, or if you have any bleeding after menopause. Tiredness or breathlessness alongside heavy periods is worth a blood test for anemia.
None of this is rare. The CDC estimates heavy menstrual bleeding affects about one in five women, and ACOG notes roughly a third of women seek treatment for it. It is common, and there are treatments, so it is the kind of thing worth raising rather than waiting out.
What to record
Note start and end dates, how often you changed products on the heaviest days, whether you needed double protection or night changes, approximate clot size, and symptoms such as fatigue, dizziness, or shortness of breath. MiniCycle's daily note can store these observations.
A record cannot determine the cause or urgency by itself. Notes are stored on the device by default and included in the optional CloudKit copy when iCloud Sync is enabled; use them as context for medical care, not as a diagnosis.
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