Uterine fibroids, also known as leiomyomas or myomas, are non-cancerous tumours that originate from the smooth muscle cells of the uterus, often containing varying degrees of fibrous tissue. This article explains the types, diagnosis and management of uterine fibroids. 

---

Fibroids are most frequently found in women aged 30-40, although they can develop at any age except in prepubertal girls. The size, shape, and placement of fibroids can differ significantly. They range from tiny, seed-like fibroids to large ones measuring several centimetres. These fibroids can be located inside the uterine cavity, on the outer surface of the uterus, within the uterine wall, or attached to the uterus by a stalk-like structure. Around 30-50% of women approaching menopause have leiomyomas.

Approximately 50% of myomas are asymptomatic and discovered by chance; even large myomas may not produce any noticeable symptoms. When symptoms do occur, they can vary widely depending on the location, size, and number of myomas. [1]

---

Types of uterine fibroids

Myomas are categorised into subgroups based on their anatomical relationship and position within the layers of the uterus. The location of these myomas plays a crucial role in determining the symptoms they cause and the appropriate treatment approach.

1. Intramural fibroids: These are the most common type of fibroids, developing within the muscular wall of the uterus (within the myometrium).
2. Subserosal fibroids: These extend into the peritoneal cavity from the outer surface of the uterus. They can either be sessile or attached by a stalk (pedunculated). They are typically asymptomatic, but large pedunculated fibroids may undergo torsion. In some cases, they attach to other intra-abdominal structures. Occasionally, they may adhere to the omentum, receiving blood supply from omental vessels, and eventually detach from the uterus, becoming what's known as a parasitic myoma.
3. Submucosal fibroids: These are less common than other types, making up about 5-10% of all myomas arising from the body of the uterus. They extend into the uterine cavity and may partially reside within the myometrium.
4. Cervical fibroids: These fibroids originate from the smooth muscle tissue in the cervix and are categorised based on their location as anterior, posterior, or central cervical myomas. They can exert pressure on the bladder and urethra, leading to urinary retention and increased frequency of urination.
5. Broad-ligament fibroids: These fibroids develop between the layers of the broad ligament. True broad-ligament fibroids arise from the smooth muscle tissue in the round ligament, ovarian ligament, or surrounding connective tissue, and have no direct connection to the uterus, causing it to shift medially. Pseudo or false broad-ligament fibroids, on the other hand, are subserosal myomas that originate from the lateral uterine wall and extend between the layers of the broad ligament. As they grow, they push the ureters laterally and remain attached to the uterus by a stalk. They can be misidentified as adnexal masses during pelvic examinations or imaging studies. [2]

---

Symptoms

The most common symptoms of fibroids include:

1. Menstrual symptoms: Approximately 30-40% of women with myomas experience abnormal uterine bleeding, which can be prolonged, heavy, or occur between periods. The amount of blood loss may be substantial, leading to anaemia. Menstrual irregularities are most commonly associated with submucosal and intramural myomas but can also occur with subserosal myomas.

Causes of abnormal bleeding in myomas include:

• Increase in endometrial surface area
• Enhanced vascularity of the uterus
• Disruption of normal uterine contractility
• Ulceration of submucosal myomas
• Stasis and dilation of venous plexuses
• Associated anovulation
• Concurrent endometrial hyperplasia
• Dysregulation of angiogenic factors

2. Dysmenorrhea: Secondary dysmenorrhea of a congestive nature is a common symptom, often due to increased vascularity of the uterus and venous stasis. The uterus may attempt to expel a large submucosal myoma, leading to spasmodic pain.

3. Pelvic pain/discomfort: Even large or multiple myomas may not cause pain. However, a sensation of dragging or discomfort might be felt when the myoma is sizable. Pelvic pain or pressure can occur during or between menstrual periods, and acute pain may arise if the myoma undergoes torsion or red degeneration.

4. Abdominal mass: Large myomas, particularly those reaching the size of a 20-week gravid uterus or larger, may be noticeable as an abdominal mass, especially in thinner women.

5. Pressure symptoms:

1. Urinary symptoms: Myomas, especially those on the anterior uterine wall or in the cervix, can compress nearby structures, leading to urinary issues. Large uterine bodies, broad ligaments, and cervical myomas may also press on the ureters, potentially causing hydroureteronephrosis.
2. Rectal symptoms: Less common, large myomas on the posterior wall or posterior cervix can compress the rectum, hindering complete bowel evacuation.
3. Subfertility: While a direct link between myomas and subfertility isn't definitively proven, removing myomas in women with unexplained infertility has been shown to improve pregnancy rates. Myomas are believed to interfere with conception in several ways.

6. Adverse pregnancy outcomes: Pregnancy can be adversely affected by fibroid like spontaneous miscarriage, preterm labour, malpresentation of the foetus, PPH etc. Red degeneration can occur in pregnancy. [3]

---

Diagnosis

---

Management

The management of myomas (fibroids) is influenced by several factors, including the patient's age, the severity of symptoms, and the location of the fibroids. It's noteworthy that over 50% of myomas are asymptomatic. In the past, surgical intervention was considered necessary for all fibroids larger than 12 weeks in size. However, there is no specific size threshold that mandates surgery, and each case should be evaluated individually.

For perimenopausal women, it is important to counsel them that myomas typically do not grow after menopause and may even shrink slightly. Consequently, asymptomatic myomas are often managed with an initial evaluation of size, number, and location via ultrasonography, followed by counselling, annual monitoring of symptoms and ultrasound, with intervention only when necessary.

For symptomatic myomas, management decisions are based on factors such as the woman's age, the size, number, and location of the fibroids, and whether infertility is a concern.

As a result, medical management of myomas is often unsatisfactory and is typically used only for short-term relief. Indications for medical management include young women trying to conceive, small symptomatic myomas at any age, controlling bleeding while awaiting surgery, managing bleeding while treating anaemia, women nearing menopause, and preoperative shrinking of the myomas. [4]

The medical management of myomas involves various drugs:

1. Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): Mefenamic acid is commonly used to alleviate bleeding and pain in cases of small myomas with heavy menstrual bleeding. However, it does not reduce the size of the myomas, and its effectiveness may only last for a few menstrual cycles.
2. Combination Oral Contraceptive (OC) pills: Low-dose estrogen-progesterone combination pills are another option in the medical treatment of myomas. Although myomas possess estrogen receptors, potentially leading to growth when OC pills are used, in practice, many women with heavy menstrual bleeding and small myomas respond well to this treatment. Additionally, correcting anaemia with oral iron therapy is crucial. Oral progestins can also be used to manage heavy bleeding associated with myomas. However, larger and submucosal myomas typically do not respond to hormone therapy. However, OC pills are the first line of hormonal treatment.
3. Levonorgestrel Intrauterine System (LNG-IUS): This device is most effective when the myomas are small and the endometrial cavity is not heavily distorted or enlarged. Studies have demonstrated that the LNG-IUS can significantly decrease bleeding and relieve dysmenorrhea. However, if the uterus is large or the cavity is distorted, there is a risk that the device could be expelled.
4. GnRH agonists: There is strong evidence from randomised trials that GnRH agonists can effectively reduce the size of myomas, shrink the uterus, alleviate anaemia, and lessen heavy menstrual bleeding and other symptoms. After an initial phase of stimulation, these drugs suppress gonadotropin production by the pituitary gland, leading to a state of pseudomenopause. Any of the currently available preparations can be used, but due to their adverse effects, GnRH agonists are generally limited to 3–6 months of use. Once the medication is discontinued, the myomas often return to their original size within weeks. Therefore, GnRH agonists are typically used to improve haemoglobin levels or shrink the tumour before surgery, making endoscopic procedures easier. To reduce side effects like bone loss and menopausal symptoms, "add-back" therapy with OC pills is often employed.
5. Other Medications: Additional drugs used in the medical management of myomas include danazol, mifepristone, raloxifene, ormeloxifene, gestrinone, cetrorelix, and anastrozole.

If the uterus is smaller than 14 weeks in size, a vaginal hysterectomy can be performed. Alternatively, laparoscopic hysterectomy offers a less invasive option compared to open abdominal hysterectomy. Hysteroscopic myomectomy is specifically used for submucosal myomas classified as type 0 or 1. For type 2 lesions, a two-stage procedure may be necessary. The size of the myoma should be preferably <4cm. Hysteroscopic procedures are contraindicated in cases of associated adenomyosis or other myomas requiring treatment.

New treatment options include myolysis and laparoscopic uterine artery ligation. Myolysis involves reducing the size of myomas using thermal electrodes, cryoprobes, lasers, or radio-frequency probes, although these methods are still under evaluation. Ligating the uterine artery achieves similar outcomes as uterine artery embolisation. Magnetic resonance-guided focused ultrasound surgery (MRgFUS) is another option that reduces the size of myomas and relieves symptoms, but it is an expensive treatment. [4]

---

Disclaimer- The views and opinions expressed in this article are those of the author and do not necessarily reflect the official policy or position of M3 India.

About the author of this article: Dr Nikita is an Assistant Professor in the OBGY department at SMMCHRI in Chennai.