Submucosal fibroids are the rarest type of fibroids and the greatest contributor to female infertility. They are also associated with heavy menstrual bleeding and often anemia. Today we are going to talk in detail about submucosal fibroids to become better familiar with them and what treatments are available.
How Do Submucosal Fibroids Develop?
The medical term for uterine fibroids, or “fibroids” as they are most commonly known, is uterine myomas or more specifically uterine leiomyomas. When looking at the origin of the word, a leio~myo~ma stands for a tumor or oma composed of muscle or myo where the prefix leio means smooth. In other words, uterine fibroids are benign tumors of the uterus made of its smooth muscle cells.
For reasons yet unknown, normal smooth muscle cells of the uterus mutate into abnormal ones resulting in the formation of a benign uterine tumor. Myomas develop independently and may have one or multiple nodes within the uterus which resemble rubber balls varying in size.
In the early stages, tumors are located within the uterine muscle wall but as they are stimulated by naturally occurring steroid hormones – estrogen and progesterone – they grow. A tumor’s mass can be found protruding into the uterine cavity, outside the uterus, or within the thickness of the uterine wall. The different types of myomas that can be formed are submucosal, subserosal, and intramural. Submucosal and subserosal fibroids can be sessile (directly attached) or pedunculated (attached with a stalk or stem).
There are no predisposition factors for the development of one versus another type of fibroid. However, statistically, submucosal fibroids are the least common among the three and account for about 5% of the total.
In extremely rare cases, one type of fibroids can transform into another such as in the case reported in 2018 when an intramural became a submucosal leiomyoma due to strong uterine labor contractions.
Different Nature of Submucosal Fibroids
Numerous studies have investigated the nature of different types of myomas. One study discovered that tumors of submucosal locations have higher levels of estrogen and progesterone receptors. The finding supports the idea that different leiomyomas either have different natures or evolve during their life cycle.
What Symptoms Do Submucosal Myomas Cause?
As the different types of myomas grow, they cause varied deformations of the uterus. The formation of submucosal fibroids leads to the distortion of the inner mucosal layer or the endometrium (lining of the uterus).
Throughout the menstrual cycle, the endometrium changes its thickness and vascularization. Heavy menstrual bleeding is often associated with the presence of submucosal fibroids that stretch the mucosa increasing its surface area. Clinical studies have confirmed that women with submucosal myomas have a lower level of hemoglobin and a higher risk of anemia. More protruded myomas result in lower hemoglobin levels and increased anemia.
Submucosal Fibroids and Infertility
Another complication of submucosal myomatas is they often create fertility problems. As mentioned above, myomas that grow under the mucosa protrude towards the uterine cavity and can deform the uterine wall. This and other changes in the uterus can cause issues for a woman who is trying to conceive. The fallopian tubes can become blocked or the embryo is unable to attach to the uterine wall.
Numerous studies have indicated that submucosal fibroids, of any size, contribute the most to female infertility issues.
While intramural tumors might cause fertility problems, if greater than 4 cm. Subserosal fibroids have minimal or no reproductive risks.
Submucosal Uterine Leiomyomas and Pregnancy
In addition to impacting fertility, uterine myomas can create complications during pregnancy. Risks are higher in pregnant women with submucosal and intramural myomas. Submucosal fibroids are associated with miscarriages, abnormal fetus presentation, placental previa or abruption, and fetus deformities. Delivery via C-section and post-pregnancy hemorrhaging are more likely to occur in women with submucosal tumors growing in the lower part of their uterus.
Fortunately, submucosal fibroids rarely cause severe complications and often degenerate during pregnancy. Fibroid degeneration happens due to lack of nutrition as the pregnant woman’s blood flow is redistributed. This might be accompanied by intense, but temporary pain, that can be managed.
How Are Submucosal Fibroids Diagnosed?
The first test that a woman with suspected fibroids undergoes is normally a pelvic ultrasound as it is widely accessible and fairly low cost. The ultrasound can allow the doctor to see an image of the uterus but, it does have limitations in locating and diagnosing submucosal fibroids. One limitation is that small tumors are often missed and submucosal leiomyomas are frequently misdiagnosed as uterine polyps. Another limitation of ultrasound is that the images obtained from an obese patient tend to be of poor resolution and can not be properly examined.
Submucous leiomyomas of uterus can be diagnosed via hysterosalpingography. This is real-time x-ray imaging with the usage of a thin catheter and a contrast dye for evaluating the uterine cavity. Hysterosalpingography is widely used in investigating fertility issues, and submucous myomas can also be detected. Other types of myomas would not be visible with this technique.
Alternatively, a magnetic resonance imaging (MRI) test can identify fibroids of any size, in any location, ensuring correct differentiation from other conditions. The quality of images is considerably better than any ultrasound allowing a doctor to see fibroids as small as 5 mm. This makes an MRI the most reliable and accurate diagnostic test for evaluating pelvic masses. MRI examination used to be costly but nowadays it’s comparable to the cost of USG. To schedule your MRI examination at Atlanta Fibroid Center, make an appointment online or call (770) 953-2600.
What Treatment Is Used for Submucosal Myomas?
There are three known strategies to address uterine myomas: medical management, surgery, and interventional radiology treatment. Unlike subserosal fibroids, submucosal fibroids are reported to be responsive to progesterone therapy and it is often used as a first-line treatment to temporarily manage fibroid bleeding. However, this strategy is a double-edged sword. While progesterone therapy can lighten a woman’s period, in the background the added hormonal stimulation makes the fibroids grow more rapidly.
Among surgical treatments, the most widely used for leiomyomas of submucosal location is hysteroscopic myomectomy. The procedure involves a special tool called hysteroscopic resectoscope which allows a surgeon to see the uterine cavity from the inside and provides an access channel for a wire loop to re-sect submucosal myomas with high-frequency electrical energy. The hysteroscope is inserted by a surgeon into the vagina and via the cervix, into the uterine cavity.
While hysteroscopic myomectomy is the least invasive surgical technique to address fibroids, as it preserves the uterus and does not involve incisions, it is associated with high risks. These risks include damaging healthy tissue in the uterus, or neighboring organs, and a high rate of symptom recurrence. Depending on the size and number of tumors, a few sessions may be needed to remove all of them. In addition, hysteroscopic myomectomy only treats submucous fibroids.
Uterine Fibroid Embolization
Uterine fibroid embolization (UFE) treats all types of fibroids regardless of their size, location, or number. The idea behind it is to stop the blood flow to myomas with the embolic agents and cause the fibroids to die off. At Atlanta Fibroid Center the UFE procedure is performed by one of the nation’s most experienced interventional radiologists, Dr. John Lipman, and takes approximately 30-45 minutes. UFE is a great replacement for surgical treatments as there is no hospital stay, a much shorter recovery time, the procedure is highly effective, and results are permanent.
If you are having infertility issues and/or have other symptoms of uterine fibroids, do not hesitate to schedule a consultation with one of the leading fibroid experts Dr. John Lipman by calling (770) 953-2600 or by booking an appointment online at Atlanta Fibroid Center.