Understanding Uterine Fibroids
Uterine fibroids (leiomyomas) are non-cancerous growths of the uterine muscle wall. They're extremely common — by age 50, most women will have at least one — but how much they matter depends entirely on their size, number, and location.
Not all fibroids are the same
Submucosal fibroids
Grow just under the uterine lining and project into the uterine cavity. Even small submucosal fibroids often cause disproportionate bleeding and can affect fertility, making them a common reason for hysteroscopic treatment.
Intramural fibroids
The most common type, growing within the muscular wall of the uterus itself. Can enlarge the uterus and cause bleeding, pressure, and pain depending on size and number.
Subserosal fibroids
Develop on the outer surface of the uterus and grow outward. Less likely to cause bleeding, but can press on the bladder or bowel, or cause a visibly enlarged abdomen when large.
Pedunculated fibroids
Attached to the uterus by a stalk, either inside the cavity or on the outer surface. Can cause sharp pain if the stalk twists (torsion).
The Different Types of Uterine Fibroids
A closer look at how submucosal, intramural, subserosal, and pedunculated fibroids differ — and why location matters more than most patients expect.
Dr. Peyman Banooni, MD, FACOG · Patient education
What fibroids can feel like
Roughly one in three women with fibroids will have noticeable symptoms. Recognizing these patterns is the first step toward an accurate diagnosis.
- Heavy or prolonged menstrual bleeding
- Bleeding between periods
- Pelvic pressure, fullness, or heaviness
- Frequent urination or trouble emptying the bladder
- Constipation or bowel pressure
- Pain during intercourse
- Lower back or leg pain
- Visibly enlarged abdomen
- Fatigue or shortness of breath from anemia
- Difficulty conceiving or recurrent miscarriage
When Fibroid Bleeding Becomes an Emergency
Heavy bleeding from fibroids isn't always a symptom that can wait. This case shows how multiple fibroids caused bleeding severe enough to require emergency surgery.
Dr. Peyman Banooni, MD, FACOG · Patient education
If you're currently experiencing heavy bleeding — soaking through a pad or tampon within an hour, passing large clots, or feeling lightheaded — seek immediate medical care or go to the nearest emergency room.
How Dr. Banooni evaluates fibroids
Clinical history & exam
A detailed discussion of your bleeding pattern, pain, fertility goals, and how symptoms affect daily life, followed by a pelvic exam.
Transvaginal ultrasound
The first-line imaging study to confirm the presence, size, and general location of fibroids.
MRI when needed
For larger or multiple fibroids, MRI precisely maps every fibroid before a surgical plan is finalized — critical for minimally invasive and uterus-sparing approaches.
Common fibroid questions, answered directly
What are the first signs of uterine fibroids?
The most common early signs are heavier or longer menstrual periods, spotting between periods, pelvic pressure or fullness, and more frequent urination. Some fibroids cause no symptoms at all and are found incidentally during a routine exam or ultrasound.
Can fibroids turn into cancer?
The vast majority of fibroids are benign and do not become cancerous. A cancerous version, leiomyosarcoma, is rare. Rapid growth after menopause or unusual imaging findings warrant further evaluation, which is part of a thorough workup.
Do all fibroids need to be treated?
No. Small, asymptomatic fibroids are often safely monitored with periodic imaging. Treatment is generally recommended when fibroids cause significant bleeding, pain, pressure symptoms, or affect fertility.
How are fibroids diagnosed?
Diagnosis typically starts with a pelvic exam and transvaginal ultrasound. An MRI may be added to map the number, size, and location of fibroids precisely, especially when surgery is being considered.
Get an accurate diagnosis and a real plan.
Bring your prior imaging, or start fresh with an in-office ultrasound.