Fibroids are muscle growths in the uterus. They are the most common benign tumors of the female reproductive tract. Some fibroids grow so large that patients suspect they are pregnant.
Fibroids can impair fertility or lead to infertility. This depends heavily on the fibroid’s location relative to the uterine cavity and the fallopian tubes. An assessment can only be made on a case-by-case basis. However, infertility caused by fibroids is relatively rare.
Depending on where the tumor forms, fibroids are classified into different types:
- Subserosal fibroids are located on the outside of the uterus and grow from there into the peritoneum. They may have a stalk that, in the worst-case scenario, can twist, causing the patient extreme lower abdominal pain. In this case, emergency surgery is required.
- Intramural fibroids grow within the uterine wall and are among the most common types of fibroids.
- Transmural fibroids can form from any of the uterine layers.
- Submucosal fibroids are usually small. They develop in the uterine muscle and grow into the uterine lining, leading to bleeding disorders.
- Intraligamentary fibroids develop in the connective tissue layers outside the uterus, known as the uterine ligaments.
- Cervical fibroids are extremely rare and form in the muscle layers surrounding the cervix.
Illustration of fibroids inside and outside the uterus © Tsuyna | AdobeStock
Fibroids develop from uncontrolled growth of uterine muscle cells.
The exact cause of fibroids is currently unknown. Medical professionals believe that the female sex hormone estrogen plays a role in their development. For this reason, fibroids are classified as hormone-dependent tumors.
This assumption is based on the observation that women no longer develop fibroids after menopause. If fibroids are still present in these patients, they stop growing.
It is also believed that the development of fibroids is genetically determined. Fibroids tend to run in families. Ethnicity also plays a role.
Many women have no symptoms despite having fibroids. Fibroids only become a medical condition when symptoms appear. The symptoms caused by the tumor depend on its size and location.
The most common symptoms are:
- Menstrual irregularities: Excessively heavy menstrual bleeding, periods that are too heavy or last too long, and breakthrough bleeding
- Pain during menstruation. This is often accompanied by blood clots in the uterine cavity, which are then expelled amid cramps.
Less commonly,
- Pain in the lower abdomen
- Back pain (the fibroid presses on the exiting spinal nerves)
- Kidney pain
- side stitches
- Constipation (the tumor grows toward the rectum)
- Frequent urge to urinate (the fibroid is pressing on the bladder)
- Pain during sexual intercourse
.
Inability to conceive is also one of the possible symptoms of uterine fibroids.
Fibroids can cause lower abdominal pain @ SENTELLO /AdobeStock
Fibroids often grow faster during pregnancy. This can lead to
- changes in the baby’s position,
- pain, and
- obstruction of the birth canal
. In such cases, a cesarean section is necessary. Fibroids increase the risk of miscarriage and preterm birth. In some cases, they can also lead to ectopic pregnancies.
These benign tumors can often be detected by a gynecologist through a bimanual examination of the uterus via the vagina or rectum. This method can also determine whether multiple fibroids are present.
The doctor then confirms the suspected diagnosis using an ultrasound examination (sonography). This also shows the doctor exactly where the fibroid is located and how large it is. The gynecologist usually performs the ultrasound transvaginally. Alternatively, an examination through the abdominal wall may also be considered.
Some fibroids are not clearly visible on the ultrasound image. This is the case, for example, with intramural fibroids. Therefore, magnetic resonance imaging (MRI) may also be useful in certain cases.
A hysteroscopy and a laparoscopy are also helpful. These procedures allow the doctor to determine the exact location of the fibroids and, in some cases, remove them directly during the procedure.
A blood test is another diagnostic tool. The gynecologist checks iron levels to rule out or confirm iron deficiency. Iron deficiency can result from the sometimes heavy blood loss during menstruation.
Fibroids that do not cause pain or heavy bleeding do not require treatment. In such cases, monitoring through gynecological exams every 6 to 12 months is sufficient.
Uterine fibroids are non-invasive, meaning they do not invade the surrounding healthy tissue. Therefore, they can be easily removed surgically without leaving any residual tissue behind.
However, the decision to proceed with surgery depends on
- where the fibroid is located,
- how large it is,
- what symptoms it causes,
- how severe these symptoms are, and
- the patient’s age.
Surgical Removal of Fibroids
For younger women who may wish to have children in the future, the gynecologist often removes the fibroid using laparoscopy. The fibroid is removed through tiny incisions in the abdominal wall, into which a long, thin tube (laparoscope) is inserted.
A modern procedure is embolization. In this procedure, the tumor is not removed; instead, its blood supply is simply cut off by blocking the blood vessels. This prevents the fibroid from continuing to grow, and it eventually dies off. The success rate for symptom control is about 80%.
Another innovative procedure is MR-guided high-intensity focused ultrasound. For this procedure, the patient lies on a special ultrasound machine. Its high-frequency sound waves generate enough heat to destroy the fibroid tissue. This method also has a success rate of about 80%.
For symptomatic fibroids in women who have completed their family planning, a hysterectomy is an option. This method is the only one with a 100% success rate, as it ensures that no uterine fibroids remain and that no new ones can develop.
Surgically removed fibroids of various sizes © Arjun | AdobeStock
Medical Treatment for Fibroids
Fibroids can also be treated with medication. Progestins are used for this purpose, as they slow the growth of the uterine lining. This also reduces the amount of bleeding. Progestins may also influence fibroid growth.
GnRH analogs centrally suppress estrogen production, causing the fibroids to shrink. However, this leads to menopausal symptoms, which are very distressing for most women. For this reason, this treatment is usually only used for a short period prior to a planned surgery.
The most advanced pharmacological treatment is the progesterone receptor downregulator ulipristal acetate. It can be used both prior to surgery and as long-term intermittent therapy. The side effects are significantly milder than those associated with GnRH analogs.
The choice of treatment for uterine fibroids should be determined during a specialized fibroids consultation, taking into account
- all treatment options,
- the patient’s symptoms, and
- her level of distress
.
How do uterine fibroids develop?
Uterine fibroids develop from individual muscle cells that grow uncontrollably, forming benign growths. Hormonal factors often play a role, as female sex hormones can promote the growth of fibroids.
What symptoms do fibroids cause?
Depending on their location, uterine fibroids can cause a variety of symptoms. Many fibroids do not cause any symptoms at first. However, as they grow larger, they may lead to abnormal bleeding, lower abdominal pain, or pressure on the bladder—depending on the size and location of the tumor.
How are fibroids diagnosed?
A gynecologist can often feel fibroids during a physical exam and assess them accurately using an ultrasound. In some cases, additional procedures such as a laparoscopy or hysteroscopy may be necessary to determine their exact location and number.
When do fibroids require surgical treatment?
Fibroids must be treated if they cause severe symptoms or if their growth accelerates. Surgical treatment is particularly considered when pain, bleeding disorders, or the desire to have children are affected.
