The short explanation
A period that has stretched from about five days to ten or more is a change worth getting checked. Bleeding for more than seven days is longer than usual, even when the last few days are light. Common reasons include cycles where ovulation did not happen, which can make the womb lining shed unevenly, fibroids or polyps in the womb, thyroid problems, PCOS, and side effects of hormonal contraception or an IUD. Less often, bleeding problems or changes in the womb lining are involved. Many of these causes are treatable once they are identified.
What depends on your situation
The parts of this that change from woman to woman. Uncertainty is stated, not hidden.
- The doctor will want to know when the change started, how heavy the first days are, whether you bleed between periods or after sex, and whether you feel tired or breathless. Long periods can slowly lower your iron and cause anaemia.
- A blood count, thyroid test and a pelvic ultrasound are commonly suggested. If you could be pregnant, a pregnancy test is usually done first.
- Note down your bleeding days for a couple of cycles. It helps the doctor see the pattern quickly.
What this answer cannot determine
The boundary of online education. These need a clinician who can see you.
- This answer cannot tell why your periods have become longer. That needs an examination and usually some tests, such as a scan and blood tests.
Questions for your clinician
Take these with you. You can add any of them to an appointment card.
- What could be making my periods last so much longer than before?
- Should my blood count and thyroid be checked?
- Do I need an ultrasound?
- What treatment options are there once we know the cause?
When to seek help
Clinician-approved guidance for this topic. When in doubt, being seen is never the wrong choice.
Emergency — call 112 now
- Call 112 or go to the nearest emergency department if bleeding becomes very heavy and you feel faint, dizzy or breathless.
Get help the same day
- Get care the same day if you are soaking through pads quickly or feel very weak.
Book an appointment soon
- See a doctor within a few days if the bleeding has not stopped after about two weeks.
Raise it at a routine appointment
- Book a routine appointment if periods have lasted longer than seven days for two or more cycles.
Sources
The evidence this explanation is built on.
- Heavy periods NHS
- Irregular periods NHS
- Fibroids NHS
Who wrote and reviewed this
Every AskHer answer names its author. A clinically reviewed answer also names the clinician who signed it off — if no clinician is named below, it has not been clinically reviewed.
- Author
- AskHer Editorial (AI-assisted draft) AskHer's editorial team — not an individual clinician Works in English, தமிழ், हिन्दी
- Clinical reviewer
- Nobody yet No clinician has signed this answer off, and no person on the editorial team has read it yet. That is what the “Written with AI assistance” label means. It is queued for an editor to read, and then for a clinician who works in this area. The sources it was drafted against are listed above.
- Review status
- Written with AI assistance — not yet reviewed by a person
- Last reviewed
- Not yet reviewed by a person
- Version
- 1
Correction history
Substantive changes are listed, not quietly edited away.
No corrections have been made since this answer was first published.
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