Uterine Fibroids: Symptoms, Types & Treatment

10 min read
Uterine Fibroids: Symptoms, Types & Treatment

Uterine fibroids are non-cancerous growths that develop from the muscle of the uterus.

They’re very common and many people have fibroids without ever knowing they’re there. For others, fibroids can cause heavy or prolonged periods, blood clots, pelvic pressure, frequent urination, constipation or pain.

The effect fibroids have depends less on simply having one and more on its size, number and where it is growing.

If your periods have become much heavier, you’re regularly passing large clots or you’ve developed pelvic pressure or pain, fibroids are one of several possible causes worth discussing with your GP.

Key takeaways

  • Fibroids are non-cancerous growths arising from the muscle of the uterus.
  • Many fibroids cause no symptoms and don’t require treatment.
  • Symptoms can include heavy or prolonged periods, blood clots, pelvic pressure, painful periods, frequent urination and constipation.
  • Where a fibroid grows can be just as important as its size.
  • Ultrasound is commonly used to investigate suspected fibroids.
  • Treatment ranges from monitoring and medicines to procedures that shrink or remove fibroids.
  • Future pregnancy plans are an important part of choosing treatment.

On this page

What are uterine fibroids?

Fibroids, also called leiomyomas or myomas, are non-cancerous growths made from muscle and fibrous tissue.

They grow in or around the uterus and can range from very small growths that are only discovered during an ultrasound to much larger fibroids that change the size or shape of the uterus.

You can have one fibroid or many.

Having fibroids doesn’t automatically mean you’ll have symptoms or need treatment.

What are the different types of fibroids?

Fibroids are usually described according to where they grow.

Intramural fibroids

Intramural fibroids grow within the muscular wall of the uterus.

Depending on their size, they may contribute to heavy periods, pain or a feeling of pelvic pressure.

Submucosal fibroids

Submucosal fibroids grow towards or into the cavity of the uterus beneath the uterine lining.

Because they affect the space where the endometrium grows and sheds, even relatively small submucosal fibroids can sometimes contribute to heavy or irregular bleeding.

Subserosal fibroids

Subserosal fibroids grow towards the outside of the uterus.

They may cause relatively little menstrual bleeding but can create pressure symptoms if they become large enough to press on the bladder, bowel or surrounding structures.

Pedunculated fibroids

A pedunculated fibroid grows on a stalk and can project either into the uterine cavity or towards the outside of the uterus.

What symptoms can fibroids cause?

Many fibroids cause no symptoms at all.

When symptoms do occur, they can include:

  • heavy periods
  • periods lasting longer than usual
  • passing larger or more frequent blood clots
  • painful periods
  • bleeding between periods
  • pelvic heaviness or pressure
  • lower abdominal or lower back discomfort
  • pain during sex
  • needing to urinate more frequently
  • constipation or pressure on the bowel
  • abdominal enlargement when fibroids are large

The number and severity of symptoms don’t always match fibroid size. A small fibroid projecting into the uterine cavity may cause significant bleeding, while a larger fibroid growing outwards may cause pressure rather than heavy periods.

Can fibroids cause period blood clots?

Yes. Fibroids can contribute to heavy menstrual bleeding, and heavier bleeding makes visible menstrual clots more likely.

This doesn’t mean everyone who passes clots has fibroids.

Small clots can occur during normal periods. It becomes more worth investigating when you’re frequently passing larger clots alongside heavy or prolonged bleeding, increasing pain or a significant change from your usual period.

Australian guidance uses regularly passing clots larger than a 50-cent coin as one possible sign of heavy menstrual bleeding.

Read our guide to period blood clots and what’s normal for more.

What causes fibroids?

We don’t fully understand why fibroids develop.

Oestrogen and progesterone appear to influence their growth, which helps explain why fibroids usually develop during the reproductive years and often shrink after menopause.

Family history and genetics also appear to play a role.

Fibroids aren’t caused by anything you did wrong and there is no proven lifestyle change that guarantees you won’t develop them.

How are fibroids diagnosed?

Your doctor will usually begin by asking about your periods, pain, pressure symptoms, fertility plans and medical history.

A pelvic ultrasound is commonly used to look for fibroids and assess their:

  • size
  • number
  • location
  • relationship to the uterine cavity

A transvaginal ultrasound may give a clearer view of the uterus. You should be told what the examination involves and asked for your consent.

Other investigations may sometimes include MRI, saline ultrasound or hysteroscopy, particularly when a fibroid is thought to project into the uterine cavity.

If you have heavy periods, blood tests may also be recommended to check for iron deficiency and anaemia.

Fibroids, adenomyosis, endometriosis and polyps: what’s the difference?

Condition What it involves Common symptoms
Fibroids Non-cancerous growths arising from uterine muscle Heavy bleeding, pressure, pain, clots
Adenomyosis Endometrial-like tissue growing within the muscle of the uterus Heavy painful periods, pelvic pain, clots
Endometriosis Endometrial-like tissue growing outside the uterus Pelvic pain, painful periods, painful sex and other symptoms
Uterine polyps Growths arising from the lining of the uterine cavity Irregular bleeding, bleeding between periods and sometimes heavy periods

It’s also possible to have more than one of these conditions at the same time.

Read more about endometriosis, adenomyosis and uterine polyps.

How are fibroids treated?

Fibroids don’t always need treatment.

If they aren’t causing symptoms, monitoring may be all that is required.

If symptoms are affecting your life, treatment depends on:

  • how heavy your bleeding is
  • pain or pressure symptoms
  • fibroid size, number and location
  • your age and stage of life
  • whether you want to become pregnant in the future
  • your preferences

Medicines for bleeding and pain

Medicines used for heavy menstrual bleeding may include tranexamic acid and anti-inflammatory medicines such as ibuprofen, naproxen or mefenamic acid where suitable.

Hormonal treatments, including hormonal contraception and a levonorgestrel-releasing hormonal IUD, may also reduce bleeding for some people.

Whether an IUD is suitable can depend on whether fibroids significantly distort the uterine cavity.

Medicines that affect fibroid growth

Some hormonal medicines can temporarily reduce fibroid size or symptoms.

These are usually prescribed for specific situations, such as before surgery or when other treatments aren’t suitable.

Myomectomy

A myomectomy removes fibroids while leaving the uterus in place.

The surgical approach depends on the size and location of the fibroids and may involve hysteroscopy, laparoscopy or abdominal surgery.

Myomectomy may be considered when maintaining fertility or the uterus is important.

Uterine artery embolisation

Uterine artery embolisation is a procedure performed by an interventional radiologist.

Small particles are introduced into the arteries supplying the fibroids, reducing their blood supply so that they shrink.

It isn’t suitable for everybody, particularly where future pregnancy is a major consideration, so the benefits and risks need to be discussed individually.

Focused ultrasound

Focused ultrasound may be available for selected fibroids. It uses concentrated ultrasound energy to treat fibroid tissue without conventional surgery.

Suitability depends on factors including fibroid location and available services.

Hysterectomy

A hysterectomy removes the uterus and therefore permanently prevents fibroids from recurring.

It is major surgery and is generally considered when symptoms are significant and other treatment options aren’t appropriate or haven’t helped.

Can fibroids affect fertility or pregnancy?

Most people with fibroids can become pregnant.

However, some fibroids can make conception more difficult or affect pregnancy, particularly when they distort the inside of the uterine cavity.

Fibroids have also been associated with an increased risk of some pregnancy complications.

If you have fibroids and are trying to conceive or planning pregnancy, discuss the size and location of your fibroids with your doctor or fertility specialist before deciding on treatment.

When should you see a doctor?

Talk with your GP if you have:

  • heavy or prolonged periods
  • frequent large blood clots
  • bleeding between periods
  • pelvic pain or pressure
  • pain during sex
  • new bladder or bowel pressure symptoms
  • difficulty becoming pregnant
  • persistent tiredness, weakness, dizziness or shortness of breath that could suggest iron deficiency

A significant change from what is normal for you is worth checking even if your symptoms don’t fit neatly into a particular diagnosis.

Frequently asked questions

Are uterine fibroids cancerous?

Fibroids are benign, or non-cancerous, growths. A rare uterine cancer called leiomyosarcoma can arise from uterine muscle, but this is considered a different disease rather than an ordinary fibroid simply turning into cancer.

Do fibroids always cause heavy periods?

No. Many fibroids cause no symptoms at all. Fibroids that affect or distort the uterine cavity are more likely to contribute to menstrual bleeding than some fibroids growing towards the outside of the uterus.

Can fibroids cause large blood clots?

They can contribute to heavy menstrual bleeding, which can make larger clots more likely. Blood clots alone don’t prove you have fibroids.

Can fibroids make you look pregnant?

Very large or numerous fibroids can enlarge the uterus and abdomen. Smaller fibroids usually don’t cause a visible change.

Do fibroids go away after menopause?

Fibroids commonly shrink after menopause as ovarian hormone levels fall and symptoms often improve, although this isn’t guaranteed. New bleeding after menopause should always be assessed rather than assumed to be caused by an existing fibroid.

Can you have fibroids and adenomyosis together?

Yes. Fibroids and adenomyosis are different conditions but can occur together, which can make symptoms such as heavy bleeding and period pain more complex.

Do all fibroids need to be removed?

No. Fibroids that aren’t causing troublesome symptoms often need no treatment. Treatment decisions should be based on symptoms, fibroid location and size, fertility plans and your preferences rather than the presence of a fibroid alone.

Fibroids are common, but troublesome symptoms deserve attention

Finding out you have fibroids doesn’t automatically mean surgery is in your future.

Many fibroids never cause a problem.

But if your periods are becoming progressively heavier, you’re passing large clots, living with pelvic pressure or planning your life around bleeding, you deserve more than being told that heavy periods are simply something to put up with.

There are several treatment options, and the right one depends on your body, symptoms and priorities.

Related reading

Sources and further reading

This article provides general educational information and isn’t a substitute for individual medical advice.