Why Do I Get Period Blood Clots?

You might notice that when you’re having your period, you’re also passing blood clots at the same time. But what’s the meaning behind them? Why do we get period blood clots during our time of the month? Are they anything to be worried about?

Below, we’ve set out some useful info on everything you need to know about period blood clots, what’s normal and what isn’t, and what you can do if you think something might be wrong. Spoiler alert: it’s time to go and speak to your doctor!

Is passing blood clots during a period normal?

For most of us, passing blood clots occasionally during a period will be completely normal. They’re made up of blood and the lining that builds up in your uterus in preparation for pregnancy, and the body is simply getting rid of it when you have your period and don’t get pregnant. 

Blood clots will normally happen when you’re having a particularly heavy menstrual flow, and are more common in the first two days of your cycle. These are usually the heaviest days of every month, so you’ll be more likely to pass them then.

Like your actual period, blood clots can also vary in colour from bright red to darker and closer to brown. This is because the blood passed later in your period is older and is leaving the body more slowly than it would’ve done at the start.

On occasion, the clots closer to the end of your period might also be bright red, but this doesn’t mean that anything is wrong ‒ it just means this blood hasn’t had time to darken because it’s flowing quickly.

If you’re more likely to have a heavy flow, excessive bleeding and clots forming can last for a bit longer than normal. If they’re small (no larger than a 10p coin) and only happen occasionally, there’s no need to worry about it.

What if I pass large blood clots during a period?

Period blood clots are not life threatening, but if you’re passing clots larger than a 10p coin during a period, then you might want to have a chat with your doctor about what this could mean. Having consistently heavy menstrual bleeding and frequently passing big blood clots could be a symptom of an underlying problem.

Some indications that you go through heavy periods include:

• You have to change your pad or tampon every couple of hours
• You regularly bleed through clothes or bedding
• You feel the need to wear more than one menstrual product at once (e.g. wearing a pad and a tampon at the same time)

If you’re passing blood clots (typically with pain or cramping) and think you could be pregnant, please speak with a doctor or another medical professional right away. This could be a sign of a miscarriage.

How do period blood clots form?

Your period starts when hormones are triggered that make your body shed the lining of the uterus. When this lining sheds, small blood vessels will bleed as well. 

To protect your body and to prevent too much blood from being lost, your body forms blood clots. These are made up of a combination of plasma (meaning the liquid part of your blood) and platelets (tiny blood cells that bind together to form the clot). You’ll also find bits of tissue from the uterine lining mixed in more often than not.

You’ll usually find that you’re passing big blood clots when you’re on your heavier days because there’s a larger amount of blood sitting in the uterus. This might also mean that your period will come with pain and cramping that you might not get on your lighter days, as the cervix needs to dilate more to pass large clots.

What causes period blood clots?

The causes behind particularly heavy periods and getting more period blood clots can change, depending on your age and medical history. Some of the reasons you may be getting big period blood clots more often include:

• Uterine fibroids (noncancerous growths in the uterus)
• Endometriosis (when the tissue in your womb lining grows outside the uterus, usually in the ovaries or the fallopian tubes)
• Adenomyosis (when the tissue in the womb lining grows into the uterine wall, making the uterus larger)
• Hormonal imbalances (anything from PCOS to hypothyroidism and menopause)
• Bleeding disorders (like platelet function disorder or Von Willebrand Disease)
• Cervical or uterine polyps (growths in the uterus or cervical canal)
• Going through a miscarriage
• Having cancer in your uterus or cervix

Getting blood clots after a period

You might spot signs of blood clots or bleeding after a period, and there are many things that could be causing this. Not all of them will be something to worry about, either. For example, it’s completely natural to have some irregular bleeding or spotting between periods if you’ve just started new hormonal contraception, if you miss taking your contraceptive pill, or if you’ve recently had an injury to your vagina (including from penetrative sex). 

If you are worried that blood clots after a period have already been and gone might be something else, the best thing that you can do is talk to your doctor. They’ll be able to talk to you about your symptoms and may set up a test for diagnosis.

Diagnosing period blood clots

If you’re called to see your doctor about your blood clots, they might start by asking you a few simple questions such as:

• How long does your period last?
• How heavy is your usual flow?
• Have you noticed any changes in your flow over time?
• Do you use birth control? What kind?
• What other medications are you on?
• Have you ever been pregnant before?
• Have you ever had surgery on your pelvic area?

The doctor might also recommend a pelvic exam, and want to do some tests that could help them to work out what is causing your blood clots. These tests include:

• Blood tests (meaning they can look at your thyroid function and check for hormonal imbalances, anaemia, and any issues with how your blood clots)
• CT scans
• Endometrial biopsies (samples of your uterine lining are removed to look for abnormal cells)
• Hysteroscopies (a thin scope with a light is inserted so the doctor can examine your uterus)
• Pap smears (cells are taken from the cervix to see if any changes are the cause of the clotting)
• Sonohysterograms (fluid is injected into your uterus to examine the lining)
• MRI scans
• Ultrasounds

Treating period blood clots

Treatment for large period blood clots can vary, depending on a number of different factors. These might include:

• What’s causing the clots or the bleeding in the first place
• How severe they are
• Whether or not you’re experiencing these period symptoms with pain
• Your age
• Where you are in your reproductive journey (whether you’ve had kids or not)

The usual routes for treating period blood clots and heavy periods are based on medication or surgery, especially if they’re having a knock-on effect. 

For example, if your periods are making you anaemic, your doctor may decide to put you on iron supplements to help manage the symptoms. They might also decide that you’ll benefit from going on the Pill, having hormonal therapy, or taking medicines that help to reduce your bleeding.

Different types of surgeries might also be offered if medication doesn’t work, or if you need polyps or fibroids removed. 

Taking care of your symptoms while on your period

You know how best to manage your own period, and taking care of yourself while you’re on your more delicate days should (of course) be your priority. That’s why it’s important to make sure you’re handling your symptoms even on your heaviest days, by doing things such as:

• Taking painkillers such as ibuprofen
• Staying hydrated with lots of water
• Eating a healthy, balanced diet with plenty of iron-rich foods (like leafy greens, red meat, quinoa, and tofu)
• Keeping an eye on where the nearest toilets are if you’re out and about, so you can get there quickly if need be
• Wearing dark coloured clothing if you’re worried about leaks
• Keeping comfortable and doing something that you love, to make yourself feel that little bit better!

Stay comfortable and leak-free on any kind of flow

We don’t want you to have to go through every menstrual cycle with pain and constant worries about leaks or blood clots. That’s why we’ve got our own sets of Heavy and Super Heavy flow period pants for sale here at FLUX Undies!

Our multi-layer technology means that our soft, comfortable undies can hold between four and five tampons’ worth of flow, so you’re always guaranteed a stress (and leak!) free day! Each pair is designed to be worn for up to eight or twelve hours at a time, too, so you can even sleep safe and sound knowing that you’ll wake up to clean sheets in the morning.

Why not get yourself started with a couple of pairs you can wear overnight or at the weekend and see how they work? We’ve got a 60 day money-back guarantee if you’re not totally satisfied by the end of it!