Menstrual Health Centre

Heavy menstrual bleeding

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Confidence comes from the facts

Heavy bleeding can affect many of us at some stage in our lives, even if it’s only for a few menstrual cycles, or months. Some women experience heavy bleeding for most of the years they menstruate, simply because their bodies work that way. To doctors, heavy bleeding is anything over 80 ml a month - or, more than a quarter of a normal sized can of cola.

The medical term for very heavy bleeding is Menorrhagia. It’s often caused by the lining of the uterus - or womb - becoming unusually thick. In a minority of cases, maybe 40%2, it can be caused by medical conditions like thyroid problems3 - so it makes sense to be aware of the facts. Heavy bleeding can even be caused by intrauterine contraceptive devices, or IUDs. You may know IUDs are also known as 'the coil', a type of contraceptive device inserted internally. Blood loss may increase by 40-50% after an IUD is inserted4.

How does heavy bleeding occur?

Every month, before an egg is released from the ovaries, the uterus begins to prepare for it. It builds up a thicker lining around its walls, a little like a cushion. Most eggs aren’t fertilised. When the egg is unfertilized, the uterus begins to lose its lining after a few days. We experience this as the blood flow that comes once a month - it’s menstruation, or our period. Some of us simply have a thicker and heavier lining in our uterus than others, so we bleed more heavily.

Doctors think that perhaps 40% of women bleed heavily because of an illness5, so heavy bleeding should always be checked out with your GP if you experience it for more than one or two menstrual cycles. Most problems are quite minor, and most can be treated relatively easily6. So, a doctor’s visit can help you to feel better, and relieve any worry.

Some of the medical causes of heavy bleeding can include7:

Blood clotting disorders. Blood clotting disorders are problems that anyone, male or female, can have. They tend to be rare. Some are brought on as side affects of medical treatment, from drugs like warfarin. Others can be produced ‘naturally’ by the body, through illnesses like von heamophilia8.

Cancer of the womb. Thankfully, one of the rarest causes of heavy bleeding is cancer of the womb. There are different types of cancer that can affect the womb, and they can be caused by many complex factors, like age, weight and genetics9.

Endometriosis. Endometriosis is when tiny sections of womb lining grow outside the uterus, like in the vagina. It can require treatment, but is not normally a serious medical condition.

Fibroids. A bit like polyps, these are ‘benign’ growths, meaning they are not cancerous - although they can cause pelvic pain and irritation.

Pelvic inflammatory disease, or PID. As the name suggest, the pelvis can become inflamed, or very sore, and this can lead to bleeding. This is normally cause by an infection, and can produce bleeding between periods, or after sexual intercourse.

Polycystic ovary syndrome, or PCOS. This is a genetic disorder, inherited from parents. Cysts are a bit like internal blisters, or little ‘sacks’ or ‘bubbles’ we can get in our bodies. They tend to be relatively harmless. ‘Polycystic’ simply means ‘many cysts’, as women with the condition have a number of cysts in their ovaries10.

Polyps. Polyps can be found in the womb or the lining of the neck of the womb, called the cervix. They are ‘benign’ growths, meaning they are not cancerous - although they can cause pain and irritation.

Taking care of your health

No one knows your body like you do. If you have unusually heavy periods that give you cause for concern, see your doctor - just to be safe. Look out for things like abnormally heavy blood flow - especially if it needs a tampon or pad change every 2 hours. Or, if you bleed for 7 days or more, or have an unusual discharge.
And, if pain or blood loss is severe, call 999 immediately. Learn more at Body Safe.

If you have heavy periods, make sure you're getting plenty of iron in your diet, with green vegetables like spinach and cabbage. If you eat meat, lean red meat like steaks can provide lots of iron. Vegetarians can choose iron-rich pulses.

And don’t forget that if you experience pain during your period, you don’t have to suffer in silence.

Feminax Ultra was the first maximum strength naproxen pain reliever available in the UK without prescription and it’s specifically for period pain. Feminax Ultra works directly at the site of pain to reduce the uterine prostaglandins which are the cause of period pain and it will provide relief from period pain for up to 8 hours. So even if your blood flow is heavy, you can at least manage the pain with Feminax.

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  3. 3 Daniels, Patricia, et al. 2007. Body: The Complete Human. Washington, D.C.: National Geographic Society.
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