The short answer: small clots are a normal part of many periods, especially on heavy days. Clots that are bigger than about 2.5 cm, roughly a ₹10 coin, or that show up every period along with very heavy bleeding, are a reason to see a gynaecologist.
Why period blood clots at all
Your body has a built-in system to stop bleeding. Normally, when you have a period, your womb releases substances that keep the blood thin so it can flow out easily. On heavy days, blood can pool and leave faster than those substances can work. Some of it thickens into soft, jelly-like lumps. That's a period clot.
Clots can be bright red, dark red or almost black. Some contain small bits of womb lining, which is normal too.
The ₹10 coin test
You don't need to measure anything precisely. Next time you notice a clot, compare it with a coin:
- Smaller than a ₹1 coin: very common, especially on days one and two. Usually nothing to worry about.
- Around the size of a ₹10 coin (about 2.5 cm) or larger: worth noting down and discussing with a doctor, particularly if it happens most months.
- Many clots every period, or clots alongside very heavy bleeding: book an appointment.
Keep a quick note on your phone: the day of your period, the size, and how many. Over two or three cycles, this gives your doctor a clear picture.
What causes large or frequent clots
When clots are big or frequent, it's usually because the flow itself is heavy. Common reasons include:
- Fibroids: non-cancerous growths in the womb that can make the lining larger and bleeding heavier
- Adenomyosis: the womb lining grows into the muscle wall, often causing heavy, painful periods
- Endometriosis: tissue like the womb lining grows outside the womb
- Polyps: small growths on the lining of the womb or cervix
- Hormone changes: a cycle without ovulation, PCOS, thyroid problems, or the years before menopause
- Bleeding disorders: conditions such as von Willebrand disease, especially if you also bruise easily or have nosebleeds
- A miscarriage: if there's any chance you could be pregnant, large clots or grey tissue need a same-day check
Signs that need a doctor soon
See a gynaecologist if any of these apply:
- Clots larger than about 2.5 cm, more than once
- You soak through a pad or period panty every one to two hours
- Your period lasts longer than 7 days
- Severe cramps that painkillers don't ease
- Tiredness, breathlessness or dizziness, which can be signs of anaemia
Go to a doctor the same day if you are pregnant or might be, or if you feel faint, very weak, or your heart is racing.
What to expect at the doctor's
Your gynaecologist will ask about your cycle and how heavy your periods are. They may examine you and suggest a pelvic ultrasound to look at the womb. Blood tests can check for anaemia, thyroid problems or a clotting issue. Treatment depends on the cause. It can range from medicines that reduce bleeding to removing a fibroid or polyp.
Managing clot-heavy days
Clots usually come with heavier flow, so these days need more coverage:
- Choose fuller coverage. A high-waist period panty or period shorties give more area to catch clots when you sit or lie down.
- Change when you go to the toilet. Clots can come out in a rush when you stand up after sitting for a while. A quick change at that time helps.
- Rinse cold, then wash. Rinse your period panty in cold water to clear clots before washing as usual.
- Eat iron-rich foods. Heavy, clotty periods use up iron. Include leafy greens, rajma, chana, ragi, eggs or meat.
Frequently asked questions
Are period clots the same as miscarriage tissue? Not usually. Period clots are soft and red to dark. Miscarriage tissue can look grey or white and is often accompanied by cramping and heavy bleeding. If you could be pregnant, see a doctor right away.
Why do I pass a clot when I stand up? Blood collects in the vagina while you're sitting or lying down and partly thickens. When you stand, gravity releases it all at once.
Can clots be stopped at home? There's no home remedy proven to stop clots. If they bother you, see a doctor, as the treatment depends on the cause.
Are clots normal after a baby? Clots are common in the first weeks after childbirth. Large clots, or any clot with fever, foul smell or severe pain, should be checked by your doctor.
Related reading
- Heavy Periods: How Much Bleeding Is Too Much?
- Period Blood Colour Chart: What Each Shade Means
- Bleeding Again After Your Period Ended? What It Means, by Timing
This article is for general information and doesn't replace advice from your doctor.
Sources: NHS: Heavy periods (clot size guide and causes), NHS: Periods