Uterine Fibroids (Leiomyoma): Types, Causes, Symptoms, Diagnosis, Treatment and Nursing Management

Fibroids vary considerably in number, size and location. A woman may have a single small leiomyoma or numerous tumours that substantially enlarge and distort the uterus.

Their clinical importance depends not simply on their size, but also on their number, anatomical location, relationship to the endometrial cavity and surrounding organs, symptoms and the patient's reproductive goals.

Some fibroids remain asymptomatic and are discovered incidentally during pelvic examination, ultrasound, pregnancy assessment or surgery. Others cause significant menstrual bleeding, pelvic pressure, pain, anaemia or reproductive problems.

The uterus is a hollow muscular pelvic organ situated between the urinary bladder anteriorly and rectum posteriorly.

The uterine wall consists principally of three layers:

• Endometrium: the inner mucosal lining that undergoes cyclic changes during the menstrual cycle.
• Myometrium: the thick middle layer composed of smooth muscle. Uterine leiomyomas arise predominantly from this layer.
• Perimetrium: the outer serosal covering of much of the uterus.

Uterine leiomyomas are among the most common benign tumours of the female reproductive tract. Many are clinically silent, meaning the true frequency is greater than the number of symptomatic cases presenting to hospitals.

They occur predominantly during the reproductive years and often become less clinically prominent after menopause, reflecting the important influence of ovarian hormones on fibroid biology.

The exact cause of uterine fibroids is complex. Their development appears to involve genetic alterations in myometrial cells, hormonal influences and changes in extracellular matrix and local growth signalling.

A leiomyoma develops from abnormal proliferation of uterine smooth muscle cells together with accumulation of extracellular matrix components.

Oestrogen and progesterone influence the growth and maintenance of fibroids. This helps explain why leiomyomas occur predominantly during reproductive life and often decrease in size after menopause.

Fibroids contain abundant extracellular matrix, including collagen and other structural proteins. This contributes to their typical firm consistency.

Somatic genetic abnormalities have been identified in different groups of leiomyomas. Fibroids therefore represent biologically heterogeneous tumours rather than one identical molecular process in every patient.

• Increasing reproductive age until menopause.
• Family history and genetic susceptibility.
• Earlier menarche has been associated with increased risk.
• Higher body weight can be associated with increased risk.
• Hormonal and reproductive factors influence fibroid biology.

A practical anatomical classification divides fibroids into submucosal, intramural, subserosal, pedunculated and less common sites such as cervical leiomyomas.

These project toward or into the endometrial cavity. Because they distort the cavity, even relatively small submucosal fibroids may produce significant abnormal uterine bleeding and may affect reproductive outcomes.

Intramural leiomyomas are located predominantly within the myometrium. They can enlarge the uterus and may cause heavy menstrual bleeding, pressure symptoms or pain depending on their size and relationship to the endometrial cavity.

These grow predominantly toward the external surface of the uterus. Large lesions can produce pressure symptoms involving adjacent pelvic structures.

Some submucosal or subserosal fibroids develop on a stalk. A pedunculated subserosal fibroid projects outward from the uterus.

A minority of leiomyomas develop within the cervix. Depending on size and position, these may produce pelvic pressure or complicate surgical or obstetric management.

Grossly, a typical leiomyoma is a firm, well-circumscribed, round or oval mass.

When cut, the tumour classically demonstrates a whorled appearance caused by interlacing bundles of smooth muscle and fibrous tissue.

Fibroids may undergo secondary changes, particularly when their blood supply becomes insufficient for their size.

Microscopically, conventional leiomyomas consist of intersecting fascicles of relatively uniform spindle-shaped smooth-muscle cells. The cells typically have elongated nuclei and eosinophilic cytoplasm.

The pathological assessment is important because other smooth muscle tumours and variants may have different biological behaviour.

A fibroid can outgrow portions of its blood supply, producing degenerative changes.

Many uterine fibroids cause no symptoms. When symptoms occur, their pattern depends on the number, size and location of the tumours.

Heavy menstrual bleeding is one of the most important clinical presentations. Prolonged or excessive bleeding may eventually produce iron-deficiency anaemia.

An enlarged fibroid uterus can cause a sensation of pelvic heaviness, pressure or abdominal enlargement.

A sufficiently large or appropriately positioned fibroid may exert pressure on the bladder, contributing to urinary frequency or other urinary symptoms.

Posterior or large pelvic fibroids may contribute to rectal pressure or constipation in some patients.

Fibroids may cause pelvic discomfort, dysmenorrhoea or pain. Sudden significant pain may occur with certain complications or degenerative changes and requires appropriate assessment.

Large or multiple fibroids can enlarge the uterus sufficiently to produce visible or palpable lower abdominal enlargement.

The relationship between leiomyomas and fertility depends strongly on fibroid location and distortion of the uterine cavity.

Submucosal fibroids are particularly important because they alter the endometrial cavity. Other fibroids may also be relevant in selected patients depending on their size and anatomical relationship to the cavity.

Fertility management should therefore be individualised rather than assuming that every fibroid causes infertility.

Many pregnancies with fibroids progress without major complications. Nevertheless, size, number and location can affect pregnancy in some patients.

Potential associations can include pain from degeneration, abnormal fetal lie or presentation, placental problems, preterm birth, labour difficulties and postpartum haemorrhage in selected cases.

Important points include the menstrual pattern, duration and severity of bleeding, passage of clots, pelvic pain, pressure symptoms, urinary or bowel complaints, reproductive history, pregnancy intentions and previous treatment.

Large fibroids may produce an enlarged, irregularly contoured uterus. The examination should be interpreted together with imaging and the overall clinical picture.

Pregnancy should be considered where clinically appropriate in a patient presenting with abnormal uterine bleeding.

A full blood count is particularly important when heavy menstrual bleeding is present because chronic blood loss may cause anaemia.

Assessment for iron deficiency may be appropriate in patients with significant or prolonged menstrual blood loss.

Ultrasound is a central imaging investigation for suspected fibroids. Transabdominal and/or transvaginal approaches can identify the number, size and location of leiomyomas and assess their relationship to the uterus and endometrial cavity.

MRI provides detailed soft-tissue characterisation and mapping of fibroid size, number and location. It can be particularly useful when detailed anatomical assessment is needed before selected procedures or when ultrasound findings are insufficient.

Hysteroscopy allows direct visualisation of the uterine cavity and can be particularly useful for evaluating and treating selected intracavitary or submucosal lesions.

• Adenomyosis.
• Endometrial polyp.
• Pregnancy-related uterine enlargement.
• Ovarian or adnexal mass.
• Endometrial pathology.
• Other causes of abnormal uterine bleeding.
• Other uterine or pelvic tumours.

Management is individualised according to the severity of symptoms, fibroid location and size, anaemia, age, reproductive plans, desire for uterine preservation and previous treatment.

An asymptomatic or minimally symptomatic patient may not require immediate intervention. Appropriate clinical follow-up can be used when there is no indication for active treatment.

Medical treatment is principally directed toward controlling symptoms, particularly abnormal uterine bleeding and pain, and correcting associated iron deficiency or anaemia.

Depending on individual clinical circumstances, clinicians may consider hormonal and non-hormonal approaches to control heavy menstrual bleeding.

Gonadotropin-releasing hormone–based therapy may also be used in selected circumstances to suppress ovarian hormonal stimulation and reduce fibroid-related symptoms or size temporarily. Treatment selection requires professional assessment because benefits, contraindications and adverse effects differ between therapies.

Myomectomy removes fibroids while preserving the uterus. It is an important surgical option for selected patients, particularly when uterine preservation or future fertility is a priority.

The surgical approach depends on fibroid location, size, number and available expertise.

• Hysteroscopic myomectomy.
• Laparoscopic myomectomy.
• Open abdominal myomectomy.

Hysterectomy removes the uterus and provides definitive treatment for uterine fibroids in appropriately selected patients who do not require future uterine fertility.

Uterine artery embolisation is a uterus-preserving interventional procedure in which the blood supply to fibroids is reduced, resulting in fibroid ischaemia and subsequent shrinkage.

Suitability depends on individual clinical and reproductive considerations and requires specialist evaluation.

Other selected techniques include radiofrequency ablation and image-guided focused ultrasound approaches. Availability and suitability vary considerably between healthcare settings and individual patients.

Nursing care depends on whether the patient is receiving conservative treatment, medical therapy, an interventional procedure or surgery.

• Assess menstrual bleeding pattern.
• Determine duration and severity of heavy bleeding.
• Assess pelvic and abdominal pain.
• Assess pressure symptoms.
• Monitor vital signs when clinically indicated.
• Assess for symptoms of anaemia.
• Review laboratory results, particularly haemoglobin where relevant.
• Assess nutritional status.
• Assess emotional concerns and understanding of the condition.
• Determine reproductive goals as part of patient-centred care.

Chronic heavy menstrual bleeding may lead to iron-deficiency anaemia. Observe for fatigue, weakness, reduced exercise tolerance, dizziness, pallor and other clinically relevant features.

Monitor prescribed laboratory investigations and reinforce treatment and nutritional advice provided by the clinical team.

Assess the site, severity, duration and character of pain. Administer prescribed analgesia and reassess the response.

A significant change in the nature or intensity of pain should be reported for clinical reassessment rather than automatically attributed to a known fibroid.

For patients undergoing surgery, provide routine preoperative assessment and education according to the planned procedure and local protocol.

• Confirm completion of prescribed investigations.
• Assess haemoglobin and anaemia status where applicable.
• Explain the planned perioperative process.
• Provide psychological support.
• Complete prescribed preoperative preparation.
• Verify consent according to institutional procedure.

Following myomectomy or hysterectomy, priorities include appropriate postoperative monitoring, pain control, assessment for bleeding, wound care where applicable, mobility, hydration, urinary function and prevention of postoperative complications.

• Monitor vital signs according to postoperative protocol.
• Assess vaginal or operative-site bleeding.
• Assess pain and response to prescribed analgesia.
• Monitor fluid balance when indicated.
• Encourage appropriate early mobilisation.
• Observe the surgical wound where applicable.
• Monitor urinary function.
• Provide discharge education and follow-up instructions.

• Heavy menstrual bleeding.
• Iron-deficiency anaemia.
• Chronic pelvic pressure or discomfort.
• Urinary or bowel pressure symptoms.
• Degenerative changes.
• Reproductive problems in selected patients.
• Pregnancy-related complications in selected cases.
• Postpartum haemorrhage risk in some pregnancies.

Uterine fibroids are benign tumours, and many remain asymptomatic or manageable without major intervention.

The clinical course varies according to hormonal status, tumour location, size and number. Treatment outcomes are generally favourable when management is matched appropriately to the patient's symptoms and reproductive goals.