Heavy periods

Heavy Periods and Blood Clots: What’s Normal and What Isn’t

Clots smaller than a ten-rupee coin are usually normal. Clots larger than that, soaking through a pad or tampon every two hours, periods lasting more than seven days, or bleeding that forces you to change plans are not normal — and each has a specific, treatable cause.

The four-point test: is your bleeding actually heavy?

Most women have no idea whether their periods are heavy, because they have only ever experienced their own. If your mother bled heavily and your sister bleeds heavily, heavy feels like the baseline.

So here is an objective test. If any one of these is true, your bleeding meets the clinical definition of heavy menstrual bleeding.

1. You soak through a pad or tampon in under two hours. Not on the worst hour of the worst day — as a pattern.

2. You pass clots larger than 2.5 centimetres. A ten-rupee coin is almost exactly this size. Keep one in mind as a reference.

3. Your bleeding lasts more than seven days.

4. You need double protection, or you wake at night to change. A pad plus a cloth. A pad plus a tampon. Setting an alarm.

There is a fifth test that is not in any textbook but which I trust more than the others: has your period started deciding things for you? If you plan to travel around it, refuse invitations because of it, carry a spare set of clothes, sit differently in a meeting, or take a day off each month — then regardless of what the measurements say, something is wrong and it is worth investigating.

Minimal Invasive Surgery

Why clots form, and what size tells you

Your body produces anticoagulants that keep menstrual blood liquid as it leaves the uterus. When bleeding is fast or heavy, the blood pools faster than those anticoagulants can work, and it clots before it exits.

So clots are not an abnormality in themselves. They are a marker of volume. Small clots simply mean blood pooled briefly. Large, frequent clots mean you are losing a lot of blood, quickly.

Colour matters far less than most women think. Dark brown or blackish blood is usually just older blood that took longer to leave. It is volume, clot size and duration that matter — not shade.

What causes heavy bleeding

Internationally, gynaecologists use a system called PALM-COEIN to classify the causes of abnormal uterine bleeding. It divides them into structural causes — things you can see on a scan — and non-structural causes.

I find it useful because it stops the search too early. If the scan shows a fibroid, it is tempting to conclude the fibroid is the cause and stop looking. Sometimes the fibroid is incidental and something else is doing the damage.

Structural causes

Fibroids: Very common, and the position matters enormously. Fibroids inside the uterine cavity (submucosal) cause heavy bleeding far out of proportion to their size. Fibroids on the outer surface often cause no bleeding at all.

Adenomyosis: The uterine lining grows into the muscle wall. Classically causes periods that get heavier and more painful year on year, and a bulky, tender uterus. Frequently missed on routine scans.

Polyps: Small growths in the uterine lining. Often causes bleeding between periods or after intercourse. Usually removable in a short day-case procedure.

Cancer and precancerous change: I am naming this plainly rather than leaving it out, because leaving it out is what makes people afraid. It is a much less common cause than the others, but it is a real one — and this is precisely why heavy or irregular bleeding needs proper evaluation rather than reassurance. Any bleeding after menopause requires assessment, always, regardless of amount.

Non-structural causes

Hormonal imbalance, including PCOS, and irregular ovulation during perimenopause. In the years leading to menopause, cycles become erratic and bleeding often becomes heavier before it stops altogether.

Thyroid disorders: An underactive thyroid commonly causes heavier, longer periods. A simple TSH blood test picks it up, and treatment is usually a single tablet.

Clotting disorders: Frequently missed, particularly in younger women. If you have bled heavily since your very first period, bruise easily, or bleed excessively after dental work, mention it.

Copper IUD: A well-recognised cause of heavier periods. Worth remembering if your bleeding changed after insertion.

When to see a doctor this week, not next month

Please do not wait if any of these apply:

  • You are soaking a pad every hour for several hours
  • You feel dizzy, breathless, or your heart races on climbing stairs
  • You have fainted, or nearly fainted
  • You are passing clots larger than a lemon
  • You are bleeding after intercourse
  • You are bleeding after menopause — this always needs assessment
  • You are bleeding between periods and it is new

What the doctor will actually do

Knowing the sequence removes a good deal of anxiety.

A proper history. How many pads, how large the clots, how many days, what you have stopped doing. This is why I ask you to note it down beforehand.

An examination, including a pelvic examination.

Blood tests. Haemoglobin, and — importantly — ferritin. Ferritin measures your iron stores, and it falls long before haemoglobin does. A normal haemoglobin with a low ferritin means you are running on empty and about to become anaemic. Many women are told their haemoglobin is fine and sent away still exhausted. Ask for ferritin. Also TSH for thyroid.

A transvaginal ultrasound, which shows the uterus far more clearly than an abdominal scan.

An endometrial biopsy or hysteroscopy, where indicated — particularly if you are over forty, if bleeding is irregular, or if the scan shows a thickened lining. A hysteroscopy uses a fine camera passed through the cervix to look directly inside the uterus. It takes fifteen to twenty minutes, involves no cuts, and you go home the same day.

The treatment ladder

This is the section I most want you to read.

Treatment for heavy bleeding is a ladder. You start at the bottom and climb only as far as you need to. A great many women are advised hysterectomy having stood on the first rung for a few months.

 

Rung Treatment How it works Roughly how effective Preserves fertility Reversible
1 Tranexamic acid Slows the breakdown of clots, reducing flow. Taken only during bleeding days Substantial reduction for many women [VERIFY figure] Yes Yes
2 NSAIDs (mefenamic acid) Reduce both bleeding and pain Moderate reduction Yes Yes
3 Combined pill / progestogens Regulate the cycle, thin the lining Good for many Yes Yes
4 Hormonal IUD (Mirena) Releases hormone directly into the uterus, keeping the lining thin The most effective non-surgical option Yes Yes
5 Hysteroscopic removal Removes a polyp or submucosal fibroid causing the bleeding Very effective where that is the cause Yes n/a
6 Endometrial ablation Destroys the uterine lining Effective for the right candidate No No
7 Myomectomy Removes fibroids, preserving the uterus Effective where fibroids are the cause Yes n/a
8 Hysterectomy Removes the uterus Definitive No No
A few notes on this ladder.

Tranexamic acid is underused. It is inexpensive, taken only on bleeding days, and works well for a great many women. It is often skipped entirely.

The hormonal IUD deserves more attention than it gets. It is the most effective non-surgical treatment available for heavy bleeding, it is reversible, and fertility returns immediately on removal. There is one thing you must know before having one fitted: irregular spotting is common for the first three to six months. This is expected and it settles. But many women are not warned, panic in month two, have it removed — and abandon it exactly at the point it was starting to work. If you are going to have one, commit to six months or do not start.

Ablation is permanent and rules out pregnancy. Do not have it if there is any chance you might want a child.

Hysterectomy is rung eight. If someone has moved you from rung one to rung eight, ask what happened to the six rungs in between.

What does not work

I would rather tell you honestly than have you spend money finding out.

No herbal, ayurvedic or homeopathic preparation has been shown in good-quality trials to reduce menstrual bleeding or shrink a fibroid. Some women feel generally better on them, and I do not dismiss that. But the risk is not that the bottle fails. The risk is that eight months pass while you are bleeding heavily, and by the time you come to me your haemoglobin is six and correcting it takes far longer than preventing it would have.

If you want to try something alongside medical treatment, that is your decision. But check your haemoglobin every three months. If it is falling, please come in.

Diet will not stop heavy bleeding, though good iron intake helps you cope with it. Rest will not stop it. And “it will settle after your next pregnancy” is not a treatment plan.

Anaemia — the complication nobody mentions

This is the part I find most frustrating, because it is so common and so easily missed.

Women bleeding heavily every month for years become iron deficient. Slowly, so they never notice it happening. And because it is gradual, they attribute it to something else entirely.

The symptoms: constant tiredness. Breathlessness climbing stairs. Hair falling. Brittle nails. Poor concentration and forgetfulness. Feeling cold. Low mood. Sometimes an odd craving for ice or mud.

Almost every woman I see with these symptoms has decided it is stress, or age, or having too much to do.

Two things matter here. First, ask for ferritin, not just haemoglobin — iron stores empty long before the haemoglobin number moves. Second, correcting the iron is not the treatment. If you take iron tablets while bleeding heavily every month, you are refilling a bucket with a hole in it. Treat the bleeding and the anaemia follows.

Frequently Asked Questions

Is it normal to pass blood clots during periods?
Small clots up to about 2.5cm, roughly the size of a ten-rupee coin, are normal and simply mean blood pooled before leaving the uterus. Clots consistently larger than this, especially with heavy flow, suggest a condition such as fibroids or adenomyosis and should be evaluated.
How do I know if my periods are actually heavy?
Four signs: soaking through a pad or tampon in under two hours, passing clots larger than 2.5cm, bleeding for more than seven days, or needing to change protection overnight. Any one of these meets the clinical definition of heavy menstrual bleeding.
Why are my period clots black or dark brown?
Darker blood is usually older blood that took longer to leave the uterus, and is not in itself a danger sign. Colour matters far less than volume, clot size and duration. Focus on how much you are bleeding rather than what shade it is.
Can heavy periods make me anaemic?
Yes, and it is common and frequently missed. Persistent heavy bleeding depletes iron stores, causing fatigue, breathlessness, hair fall and poor concentration. Ask for a haemoglobin and ferritin test — ferritin can be low even when haemoglobin still looks normal.
Do heavy periods always mean fibroids?
No. Fibroids are one cause among several. Adenomyosis, polyps, hormonal imbalance, thyroid disorders and clotting disorders all cause heavy bleeding, and a normal ultrasound does not rule out a treatable cause.
Can heavy periods be treated without surgery?
Very often, yes. Tranexamic acid, NSAIDs, hormonal treatment and the hormonal IUD substantially reduce bleeding for many women. Surgery is considered when medical treatment fails or when a structural cause such as a fibroid or polyp requires removal.
Are heavy periods after 35 normal?
Common is not the same as normal. Periods becoming progressively heavier after 35 often indicate developing fibroids or adenomyosis rather than simple ageing, and are worth investigating rather than accepting.
When is heavy bleeding an emergency?
Seek immediate care if you are soaking a pad every hour for several hours, feel dizzy or breathless, faint, or pass clots larger than a lemon. Any bleeding after menopause requires prompt evaluation regardless of amount.

Not sure if your bleeding is normal?