Uterine fibroids: symptoms, causes and diagnosis
Uterine fibroids are non-cancerous growths that develop in or around the muscular wall of the uterus. They vary in size and location. Many people have no symptoms and discover a fibroid during a scan for another reason. Others experience heavy periods, pelvic pressure or pain that affects daily life. Finding out you have a fibroid does not automatically mean you need treatment. The useful first step is to understand where it is, whether it explains your symptoms and what matters to you, including any plans for pregnancy. This page explains what uterine fibroids are, the symptoms they may cause and how doctors investigate them. Book a consultation
What are the symptoms of uterine fibroids?
Many uterine fibroids cause no symptoms. When symptoms do occur, they can depend on the fibroids’ size, number and location. Common symptoms include:
- Heavy or prolonged periods, sometimes with clots. Ongoing blood loss can lead to iron deficiency or anaemia, which may leave you tired or short of breath.
- Period pain or pelvic pain, which may feel like cramping, aching or pressure in the lower abdomen.
- A feeling of fullness or pressure in the pelvis.
- Needing to urinate more often or having difficulty emptying the bladder.
- Bowel pressure or constipation, particularly when a fibroid presses on nearby structures.
What causes uterine fibroids?
The exact cause of uterine fibroids is not fully understood. Hormones, particularly estrogen and progesterone, appear to play a part in their growth. Fibroids can also run in families, although having a relative with fibroids does not mean you will develop them.
What causes fibroids to grow?
Fibroids may grow during the years before menopause, but their behaviour varies. Some grow slowly, some remain much the same size, and others shrink. Fibroids often shrink after menopause as hormone levels fall. A fibroid’s size alone does not tell us how much trouble it will cause. A smaller fibroid close to the uterine cavity may be associated with heavy bleeding, while a larger fibroid may cause pressure symptoms. Your symptoms and the fibroid’s location both matter when interpreting a scan.Types of uterine fibroids
Doctors describe fibroids by where they grow in relation to the uterine wall and cavity:
- Intramural fibroids grow within the muscular wall of the uterus.
- Submucosal fibroids grow towards or into the uterine cavity. Even a relatively small fibroid in this position may contribute to heavy menstrual bleeding.
- Subserosal fibroids grow towards the outside of the uterus. Depending on their size and position, they may cause a feeling of pelvic pressure.
- Pedunculated fibroids grow on a stalk extending from the inner or outer surface of the uterus.
How are uterine fibroids diagnosed?
If you have heavy periods, pelvic pain or pressure, your doctor will ask about your symptoms and medical history. They may recommend a pelvic examination and imaging to look at the uterus. Pelvic ultrasound is commonly used to identify fibroids and describe their size, number and location. The scan may be performed over the lower abdomen, internally, or both, depending on what needs to be assessed. MRI may be recommended when more detail is needed, particularly if there are multiple fibroids, the ultrasound findings are unclear, or a procedure is being considered. It can help map the fibroids and assess other possible causes of symptoms. If you have heavy bleeding, your doctor may also request blood tests to check for anaemia. Depending on your symptoms and circumstances, further assessment may be needed to investigate the bleeding. A fibroid seen on a scan is not always the cause of every symptom, so the imaging results need to be considered alongside your history.
When should you seek advice about uterine fibroids?
See your GP if your periods are heavy or painful, pelvic pressure is affecting your daily life, or you have concerns about fertility. Your GP can assess your symptoms and arrange investigations where appropriate. Any bleeding after menopause should be checked by a doctor, even if you already know you have fibroids. If fibroids are found, the next step depends on your symptoms, the scan findings and whether you hope to become pregnant. Fibroids that cause no symptoms may not need treatment. If treatment is worth considering, your doctor can discuss the available options with you.
Considering uterine fibroid embolisation?
Dr Ryan McConnell is a Sydney interventional radiologist who assesses patients for uterine fibroid embolisation, a procedure that aims to shrink fibroids by reducing their blood supply. Whether it is suitable depends on your symptoms, imaging and personal priorities, including plans for pregnancy.
Common questions about uterine fibroids
Are uterine fibroids and polyps the same thing?
No. Fibroids develop from the muscle of the uterus. Uterine polyps develop from its inner lining. Both can be associated with abnormal bleeding, so a scan or further investigation may be needed to identify the cause.
Can an ultrasound tell whether a fibroid is cancer?
Fibroids are non-cancerous growths. Ultrasound can show the size and location of a growth, but a scan does not answer every question about an unusual finding or abnormal bleeding. Your doctor may recommend further imaging or assessment if the findings are unclear.
Bleeding after menopause should always be assessed, even if a fibroid has previously been found.
Do uterine fibroids cause vaginal discharge?
Discharge is not usually a defining symptom of fibroids. If you notice new, persistent, foul-smelling or blood-stained discharge, speak with your doctor so the cause can be assessed rather than assuming it is due to a fibroid.