Fibroids, or myomas, are growths or benign tumours that form inside the uterus (womb). Around four in 10 women over the age of 40 years will have fibroids. It is not known why fibroids develop, but it is thought that the sex hormones, oestrogen and progesterone, play key roles. This is because fibroids rarely grow in girls before puberty and women after menopause. Pre-existing fibroids stop growing and can even shrink in women after menopause.
Often, fibroids do not cause any problems, but are occasionally associated with infertility, miscarriage and premature labour. Other problems can include heavy, long and painful periods. Treatment depends on the size, number and location of the fibroids, but can include medication, procedures done under local anaesthetic, ultrasound procedures and surgery. Fibroids rarely become cancerous.
Symptoms of fibroids
Most women with fibroids do not have symptoms. When symptoms are present, they can include:
- heavy, long and painful periods
- spotting between periods
- pain during sex
- feeling of heaviness or pressure in the back, bowel and bladder
- urinating often
- a lump or swelling in the lower abdomen.
Types of fibroids
Fibroids are categorised by their location, which includes:
- intramural – the most common type, growing in the wall of the uterus
- submucosal – growing in the lining of the uterus (endometrium), sometimes causing heavy, long and painful periods
- subserosal – growing on the outside of the wall of the uterus, sometimes appearing like long stalks.
Complications of fibroids
Fibroids can cause a range of complications, including:
- Anaemia – excessive menstrual blood loss can cause anaemia, where the body is not able to carry enough oxygen in the blood. Symptoms of anaemia include breathlessness, fatigue and paleness.
- Problems urinating – large fibroids can make the uterus bulge, pressing against the bladder. This can cause a feeling of fullness or discomfort and the need to urinate often.
- Infertility – fibroids can interfere with implantation of the fertilised egg in a number of ways. For example, the egg may try to implant into a fibroid, or fibroids may change the shape of the uterus and make it difficult for an egg to implant.
- Miscarriage and premature delivery – fibroids can reduce blood flow to the placenta or compete for space with the developing baby.
Diagnosis of fibroids
Fibroids can be detected using an ultrasound, where sound waves create a two-dimensional picture. The inside of the uterus can be seen with a hysteroscope, which is a thin tube that is passed through the cervix (entrance to the womb). A small camera may be placed at the tip of the hysteroscope to see the inside of the uterus on a monitor.
Treatment for fibroids
Treatment depends on the size, number and location of the fibroids, but can include:
- Monitoring – if the fibroids are not causing any symptoms and are not large, the condition can be watched over time for any changes.
- Medication – a combination of hormones or other medication can be used to shrink the fibroids before surgery.
- MRI and ultrasound – the MRI machine locates and monitors the fibroids, and ultrasound is used to heat up and destroy the fibroid tissue. The procedure is performed without anaesthetic, but medication is given to help with relaxation.
- Arterial embolisation – under local anaesthetic, a fine tube is passed through an artery in the arm or leg into the main artery that is supplying the fibroid with blood. The process is monitored by x-ray. Fine, sand-like particles are then injected into the artery to block the blood supply to the fibroid. The fibroid slowly dies and symptoms generally subside over a few months.
- Hysteroscopy – the fibroids are removed through the cervix using a hysteroscope (a thin tube with a light on the end, which is inserted into the vagina to examine the cervix and inside the uterus).
- Laparoscopy – or ‘keyhole surgery’. A thin tube is inserted through the abdomen to remove the fibroids.
- Open surgery – larger fibroids need to be removed through a cut in the abdomen. This procedure weakens the wall of the uterus and makes Caesarean sections for future pregnancies more likely.
- Hysterectomy – the surgical removal of some, or all, of the uterus. Pregnancy is not possible after a hysterectomy.
Where to get help
- Your doctor
Things to remember
- Fibroids, or myomas, are growths or benign tumours that form inside the uterus.
- Around 30 to 40 per cent of women over the age of 40 years have fibroids.
- Symptoms can include heavy and painful periods, infertility and miscarriage in pregnancy.
- Treatment options include the use of medication to shrink the fibroids, MRI and ultrasound, embolisation or surgical removal.
This page has been produced in consultation with and approved by:
Family Planning Victoria
Content on this website is provided for education and information purposes only. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your doctor or other registered health professional. Content has been prepared for Victorian residents and wider Australian audiences, and was accurate at the time of publication. Readers should note that, over time, currency and completeness of the information may change. All users are urged to always seek advice from a registered health care professional for diagnosis and answers to their medical questions.