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Why do I have heavy periods?

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Is it normal to have heavy periods?

Because we’re all different, everyone’s period is different. What could be considered a heavy flow to you might be normal to another woman. However if you have to change your tampon or sanitary towel every two hours, avoid light clothing when you’re on your period or notice blood on your bed sheets you could be experiencing heavy periods. The medical term for heavy periods is menorrhagia, and it can be felt along with other period symptoms.

If you’re unsure whether you have a heavy periods you can use the NHS heavy period self-assessment tool to find out whether your periods are classed as heavy. You can also talk to your GP about your symptoms and as well as advice they might be able to offer treatment.

Your periods could be considered heavy if you:

  • have to change your tampons or sanitary towels every two hours
  • avoid wearing light coloured clothes during your period
  • stop exercising while you’re on your period because you’re worried about leaking
  • need to use towels and tampons together
  • have to get up in the night to change your tampon or pad
  • change your bedding often as it is stained during your period
  • have to take time off work during your period

What causes heavy periods?

There are a number of conditions and medications that can cause heavy periods (menorrhagia), however in some cases the reasons for your heavy periods may not be identified.

Causes of heavy periods can include:

  • Your contraception especially if you are using an IUD *(intrauterine contraceptive device)
  • Polycystic ovary syndrome (PCOS) – a common condition that affects how the ovaries work
  • Fibroids – non-cancerous growths that develop around and inside the womb (uterus)
  • Endometriosis – tissue which is normally lines your womb is found around the body
  • An underactive thyroid – the thyroid gland doesn’t produce enough hormones which causes tiredness, weight gain and low moods
  • Cervical or endometrial polyps – benign growths found in the lining of your womb (uterus) and cervix
  • Blood clotting disorders
  • Medication taken to prevent blood clots
  • Medicines used for chemotherapy

What are the treatments for heavy period?

Whether you need treatment or not will depend on how your heavy periods affect your everyday life, and how serious the underlying cause is. Bleeding can vary from time to time, for example you may experience heavier periods during the menopause or after childbirth. However if your heavy periods are affecting you in a negative way you might want to seek treatment to reduce or stop your menstrual bleeding, as well as prevent anaemia.

Your GP will decide which treatment is best for you depending on your symptoms however this will generally start with medication. Please bear in mind that you might have to try a number of options and different medications before you find one that works for you. You may be prescribed a contraceptive pill which can help to lighten and stop your periods. If medication doesn’t work for you there are surgical options.

Can you lose too much blood during your period?

The average length of a woman’s period is five days however this can vary from two to seven days depending on your cycle. The average amount of blood lost during a period is 30 to 40 millilitres (ml), with 9 out of 10 women losing less than 80ml.*

Many women will also pass blood clots during their period these clots are considered to be large if each individual one is larger than a fifty pence coin. If you experience heavy periods with clots you may find that these clots appear on the heaviest days of your cycle. Your period will appear thicker than usual and you might find that you have to change your sanitary towel or tampons more often.

Heavy menstrual bleeding (menorrhagia) is considered to be 60ml or more in each cycle.** Women who experience heavy bleeding may also notice that they feel tired and run down, this could because if you’re regularly bleeding heavily your blood count might be low. You may be living with anaemia (iron deficiency), which can cause symptoms such as; lack of energy, pale skin and a shortness of breath.

Do you have heavy bleeding during menopause?

In the lead up to menopause (peri-menopause) you may experience a heavier menstrual flow than you are used to. You might feel like you’re constantly on your period, and any prolonged bleeding should be discussed with your GP. Many women note that their periods become lighter and less frequent; however this isn’t always the case for everyone.

Why is my period late?

Your menstrual cycle can vary and this completely normal. There are many reasons why your period might be late. For example stress and diet can affect your cycle or a new contraceptive pill. To find out more visit our late period guide.

Can spotting mean you are pregnant?

Spotting (light bleeding between your periods) is common within the early weeks of pregnancy; however spotting doesn’t necessarily mean that you are pregnant. If you think that you might be pregnant you can purchase a pregnancy test or visit your GP.

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