Uterine fibroids (also called myomas or leiomyomas) are benign (noncancerous) tumors of muscle tissue found in the uterus. They can enlarge and/or distort the uterus (womb) and sometimes the cervix (lower part of the uterus). They grow from the smooth muscle cells in the wall of the uterus. Fibroids can be singular or multiple and are very common.
Uterine fibroids/myomas represent the most frequent form of benign tumors of the female reproductive organs, representing one of the major women’s health issues worldwide which have health and socio-economic consequences. They are monoclonal tumors of uterine smooth muscle; thus, they originate from the myometrial stem cells and contain a large amount of extracellular matrix containing collagen, ﬁbronectin, and proteoglycans.
Fibroids usually become noticeable during the reproductive years and become smaller after menopause. Most cause no symptoms and do not require treatment. However, depending on the size and location of the fibroids in the uterus, they may cause symptoms and require treatment.
Types of fibroids
Fibroids are classified depending on their location within the uterus:
- subserosal– grow on the outside surface of the uterus
- pedunculated – grow as a separate attachment to the uterus
- submucosal – grow on the inside surface of the uterus
- intramural – grow inside the muscular wall of the uterus.
What causes fibroids?
The exact cause of fibroids is still unknown however female hormones, including oestrogen and progesterone, will promote their growth. You have a higher risk of getting fibroids if you:
- are at the later end of your reproductive years, 35 years and over
- started your periods at a younger than average age
- have never been pregnant
- are obese
- are of African descent.
Symptoms from fibroids are related to their size and location. Most women with uterine fibroids have no symptoms. The most common symptoms are abnormal uterine bleeding, pain, and pelvic pressure.
Abnormal uterine bleeding
Abnormal uterine bleeding is the most common symptom when fibroids are located in or near the lining of the uterus and is the main reason for requesting treatment for fibroids. Because abnormal uterine bleeding can be due to other conditions, such as endometrial cancer and hormonal problems, it is important that women with fibroids who experience abnormal vaginal bleeding undergo a thorough evaluation for other causes of bleeding.
A rapidly enlarging fibroid may outgrow its blood supply and degenerate, causing pain and cramping. Fibroids that are attached to the uterus by a thin stalk may twist and cause severe pain. Large uterine fibroids may also make sexual intercourse or certain actions painful. Women with fibroids may also experience painful menstrual cramps.
Large fibroids may press on nearby pelvic organs. If the fibroid presses on the bladder, which lies in front of the uterus, urinary frequency or urgency may occur. Pressure on the ureters (the tubes that transport urine from the kidneys to the bladder) can result in kidney damage if the fibroids are not removed. Fibroids in the lower uterus may put pressure on the large bowel and rectum, which could cause painful bowel movements, constipation, hemorrhoids, or altered shape of stools.
Fibroids and fertility
Most women with fibroids are able to become pregnant and have a completely normal pregnancy. However some fibroids change the shape of the inside of the uterus and may increase the likelihood of problems such as:
- difficulty falling pregnant
- premature labour and premature birth
- breech baby
- caesarean section
- haemorrhage after birth.
Fertility problems may not necessarily be caused by fibroids. If you are having any difficulties, a basic fertility check is a good idea to rule out any other possible issues.
Fibroids and pregnancy
Fibroids may grow in pregnancy and may change how the baby is positioned at the time of delivery. In addition, fibroids increase the risk for a cesarean section, miscarriage, and premature delivery. Depending on where the fibroids are located, they can also lead to problems during delivery, including bleeding and premature separation of the placenta.
Fibroids and cancer
Fibroids are almost always benign, which means they are not cancer. However, in rare circumstances a fibroid presumed to be benign may be malignant.
Diagnosis of fibroids
Uterine fibroids are often found on pelvic exam by assessing the shape and size of the uterus. Sometimes a pelvic exam alone may not be enough to distinguish a fibroid from an ovarian mass close to the uterus. In addition, smaller fibroids may not be found on pelvic exam. Imaging studies, like ultrasound, may be used to confirm the findings.
Ultrasound uses the echoes from high-frequency sound waves to create a picture of the pelvic organs. Because fibroids vary in size and location, ultrasound across the abdominal wall and using a probe placed in the vagina may be used to best see the fibroids.
Sonohysterography (SHG) is an ultrasound procedure in which the uterine cavity is outlined by a small amount of fluid which is placed in the uterus through a thin plastic tube. SHG improves the doctor’s ability to identify fibroids that protrude into or distort the uterine cavity. For more information about SHG, please see the ASRM fact sheet titled Saline infusion sonohysterography (SHG).
Magnetic Resonance Imaging (MRI)
Magnetic Resonance Imaging (MRI) uses magnetic fields to form images of the body. Once fibroids are diagnosed, an MRI may be helpful to identify their location in the uterus to determine best treatment options.
Treatment options for Fibroids
There are several treatment options for fibroids. If your fibroid tumors are severe enough that they cause certain symptoms, surgery is often the required treatment. Symptoms which justify surgery include: extremely heavy bleeding during your menstrual cycle, which causes anemia, pain which has become intolerable, abnormal bleeding, or when the location of the tumor is likely to cause further problems, i.e. infertility. Medical management may be attempted, however if not effective surgery may be required.
Surgical options for fibroids include:
• Myomectomy – is the surgical removal of each individual tumor without damage to the uterus, preserving a woman’s ability to conceive. However, fibroids may grow back and although it is possible to have a myomectomy repeated, multiple myomectomies can cause other problems such as the wall of the uterus sticking together due to scarring.
The different approaches to a myomectomy are as follows:
1. Hysteroscopic Myomectomy
2. Laparoscopic Myomectomy
3. Abdominal Myomectomy
4. Robotic Myomectomy
The best approach for an individual woman depends on the type of fibroid, symptoms, and number of fibroids.
• Hysterectomy – is commonly, the procedure of choice for fibroid tumors when a woman with symptoms has completed her family; a woman has excessively large fibroid tumors; abnormal bleeding occurs; or when the fibroids are causing problems with other organs such as the bladder or bowels. There are also different approaches to do a hysterectomy without removing the ovaries and in some cases even the cervix can by preserved.
1. Laparoscopic supracervical hysterectomy (LSH)
2. Laparoscopic assisted vaginal hysterectomy (LAVH)
3. Total Abdominal hysterectomy (TAH)
4. Total Vaginal hysterectomy (TVH)
• Uterine artery embolization (UAE) is a non-surgical option, depending on the size and number of fibroids present. In UAE the radiologist uses an x-ray camera called a fluoroscope to deliver small particles to the uterus and fibroids. These block the arteries that provide blood flow and cause the fibroids to shrink. Because the effect of uterine artery embalization (UAE) is not fully understood, UAE is typically offered to women who no longer wish to become pregnant or who want or need to avoid a hysterectomy.