Uterine Fibroids

Uterine fibroids are common, noncancerous growths that develop within or around the muscular wall of the uterus. They can vary significantly in size, number, and location. While many fibroids cause no symptoms, others may contribute to heavy menstrual bleeding, pelvic pain or pressure, urinary symptoms, or fertility concerns.

Not all fibroids require treatment. Management depends on your symptoms, the size and location of your fibroids, your reproductive goals, and your personal preferences.

The resources below will help you better understand uterine fibroids, how they are diagnosed, and the medical and surgical treatment options available.

Understanding Uterine Fibroids

Uterine fibroids, also called leiomyomas or myomas, are benign (noncancerous) growths that develop from the smooth muscle tissue of the uterus. They are extremely common, particularly during the reproductive years, and may occur as a single fibroid or as multiple growths of varying sizes.

Fibroids are influenced by reproductive hormones, including estrogen and progesterone. They may grow or change over time, although their behavior is often unpredictable. Fibroids are overwhelmingly benign (noncancerous). In very rare cases, a cancerous tumor called a leiomyosarcoma can develop in the muscular wall of the uterus and may resemble a fibroid. However, benign fibroids are not generally believed to turn into cancer.

Common Symptoms

Many patients with fibroids have no symptoms and discover them incidentally during a pelvic examination or ultrasound. When symptoms occur, they may include:

Heavy or prolonged menstrual bleeding, sometimes leading to iron deficiency or anemia
Pelvic pressure, fullness, or discomfort
Painful menstrual cramps
Frequent urination or difficulty emptying the bladder, particularly with larger fibroids
Constipation or bowel pressure
Pain with intercourse
Fertility or pregnancy concerns, depending on the size and location of the fibroids

The size of a fibroid does not always predict how bothersome it will be. A small fibroid affecting the uterine cavity may cause significant bleeding, while a larger fibroid on the outside of the uterus may cause few symptoms.

Types & Locations of Fibroids

Fibroids are classified based on where they grow in relation to the muscular wall and inner cavity of the uterus. Their location can influence the symptoms they cause and which treatments may be most appropriate.

Common Types of Fibroids

Submucosal fibroids: Grow just beneath the inner lining of the uterus and may extend into the uterine cavity. Even relatively small submucosal fibroids can cause heavy menstrual bleeding and may interfere with fertility.
Intramural fibroids: Grow within the muscular wall of the uterus. These are the most common type and may contribute to heavy bleeding, painful periods, or enlargement of the uterus.
Subserosal fibroids: Grow along the outer surface of the uterus. Larger subserosal fibroids may cause pelvic pressure, abdominal fullness, frequent urination, or bowel symptoms, but are generally less likely to cause heavy menstrual bleeding.
Pedunculated fibroids: Are attached to the uterus by a narrow stalk and may extend into the uterine cavity or outward from the uterine surface. Rarely, twisting of the stalk can cause sudden, severe pelvic pain.
- Types of Uterine Fibroids (Cleveland Clinic)
- Classifications of Uterine Fibroids (FIGO Classification System)

Why Does Location Matter?

The location of a fibroid is often just as important as its size. Fibroids that distort the uterine cavity are more likely to cause abnormal bleeding or affect fertility, while fibroids growing outward may be more likely to cause pressure on surrounding organs.

Understanding the size, number, and location of your fibroids helps guide decisions about monitoring, medications, and procedural or surgical treatment.

Diagnosing Uterine Fibroids

Uterine fibroids are often discovered during a routine pelvic examination or ultrasound, sometimes before they cause any symptoms.

Pelvic Examination: Your healthcare provider may notice that your uterus feels enlarged, irregularly shaped, or firm during a pelvic examination.
Pelvic Ultrasound: Ultrasound is the most common imaging test used to diagnose fibroids. It helps determine their size, number, and location within the uterus.
MRI (Magnetic Resonance Imaging): MRI is not routinely necessary but may be recommended when ultrasound findings are unclear, when multiple or large fibroids are present, or to help plan certain surgical procedures.
Saline Infusion Sonohysterography (SIS): This specialized ultrasound uses a small amount of sterile saline to gently expand the uterine cavity, allowing better visualization of fibroids that extend into the cavity. It can help determine whether a fibroid may be suitable for hysteroscopic removal.

In most cases, a pelvic ultrasound provides enough information to diagnose fibroids and guide initial treatment decisions.

Do Fibroids Always Require Treatment?

No! Many uterine fibroids do not require treatment, particularly if they are small or are not causing bothersome symptoms. Fibroids are overwhelmingly benign, and simply having fibroids does not mean that surgery or medication is necessary.

When Is Treatment Recommended?

Treatment may be considered when fibroids cause:

Heavy or prolonged menstrual bleeding, particularly if it leads to iron deficiency or anemia
Significant pelvic pain, pressure, or discomfort
Urinary or bowel symptoms, such as frequent urination or constipation
Fertility concerns, particularly when fibroids distort the uterine cavity
Rapidly worsening symptoms or significant uterine enlargement

What Happens If Fibroids Are Not Treated?

Fibroids may remain stable, grow, or occasionally shrink over time. Some patients live with fibroids for many years without developing symptoms or requiring treatment.

If your fibroids are not causing problems, we may recommend watchful waiting, which means monitoring your symptoms and performing additional examinations or imaging when clinically indicated. Routine repeat ultrasounds are not always necessary.

Having fibroids does not mean that you will eventually need surgery. Treatment decisions are individualized based on your symptoms, reproductive goals, and preferences.

Managing Uterine Fibroids

Treatment for uterine fibroids depends on your symptoms, the size and location of your fibroids, your age, and whether you are planning future pregnancies.

Not all fibroids require treatment. For patients with mild symptoms or no symptoms, observation may be the best approach. When treatment is needed, options range from medications to minimally invasive procedures and surgery.

An important distinction: Some treatments primarily reduce heavy menstrual bleeding without changing the size of your fibroids. Other treatments shrink or remove the fibroids themselves, which may be more helpful when pelvic pressure, pain, or urinary symptoms are your main concern.

Medications

Medications can be helpful for managing heavy menstrual bleeding and menstrual pain associated with fibroids. Most medications do not eliminate fibroids or significantly reduce their size.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): Medications such as ibuprofen or naproxen can help reduce menstrual cramping and may modestly decrease menstrual bleeding. They do not shrink fibroids.
Tranexamic Acid (Lysteda): A nonhormonal medication taken only during menstruation to reduce heavy bleeding. It does not shrink fibroids or provide contraception.
Hormonal Birth Control: Combined birth control pills, the patch, vaginal ring, and certain progestin-only methods may help regulate periods, reduce bleeding, and improve menstrual pain. They generally do not shrink fibroids.
Hormonal IUD (Mirena): A levonorgestrel-releasing IUD can significantly reduce menstrual bleeding in appropriately selected patients. It may be less effective or more difficult to place when fibroids significantly distort the uterine cavity.
Oral Progestins: Medications such as norethindrone acetate (Aygestin) may help control abnormal bleeding, although effectiveness varies.
GnRH-Based Medications: Medications that suppress ovarian hormone production can reduce menstrual bleeding and, depending on the medication, may temporarily shrink fibroids. These include injectable GnRH agonists such as Leuprolide (Lupron) and oral GnRH antagonist combinations such as relugolix/estradiol/norethindrone acetate (Myfembree). Because of potential side effects and treatment-duration limitations, these medications are generally used selectively.

Uterine-Sparing Procedures

These treatments address the fibroids themselves while preserving the uterus. However, preserving the uterus does not necessarily mean that a procedure is appropriate for someone planning future pregnancy.

Myomectomy: Surgical removal of fibroids while leaving the uterus in place. Depending on fibroid size and location, myomectomy may be performed hysteroscopically (through the cervix), laparoscopically, robotically, or through an abdominal incision. It is generally the preferred surgical option when fibroid removal is indicated for someone planning future pregnancy.
Uterine Artery Embolization (UAE/UFE): A minimally invasive procedure performed by an interventional radiologist that reduces blood flow to fibroids, causing them to shrink over time. It can improve bleeding and bulk-related symptoms. Pregnancy after UAE is possible, but reproductive outcomes are less well established than after myomectomy.
Radiofrequency Ablation (RFA): Uses controlled heat to destroy fibroid tissue, allowing treated fibroids to shrink over time. Procedures include laparoscopic RFA (Acessa) and transcervical RFA (Sonata). These may be appropriate for selected fibroids, although data regarding future pregnancy remain limited.

→ Learn more information: Fibroid Procedures

Definitive Surgical Treatment

Hysterectomy: Surgical removal of the uterus is the only definitive treatment for uterine fibroids, eliminating the possibility of fibroid recurrence. It may be considered for patients with significant symptoms who do not desire future pregnancy. The ovaries do not routinely need to be removed during hysterectomy for benign fibroids.

Choosing the Right Treatment

There is no single best treatment for everyone. Important considerations include:

Whether your primary concern is heavy bleeding, pain, or pelvic pressure
The size, number, and location of your fibroids
Whether you desire future pregnancy
Your preferences regarding medications, procedures, and surgery
Recovery time, potential side effects, and the possibility of fibroid recurrence

Your healthcare provider can help you compare the available options and choose an approach that best fits your symptoms and goals.

Fibroids, Fertility & Pregnancy

Many women with uterine fibroids are able to conceive naturally and have healthy, uncomplicated pregnancies. However, depending on their size, number, and location, some fibroids may affect fertility or increase the risk of certain pregnancy complications.

How Do Fibroids Affect Fertility?

The location of a fibroid is often more important than its size when considering fertility.

Submucosal fibroids, which extend into or distort the uterine cavity, are most likely to interfere with embryo implantation and increase the risk of miscarriage.
Intramural fibroids may affect fertility, particularly when they are large or distort the uterine cavity. The impact of smaller fibroids that do not distort the cavity is less clear.
Subserosal fibroids, which grow along the outside of the uterus, generally have little effect on fertility.

Not everyone with fibroids needs treatment before trying to conceive. In certain circumstances, surgical removal of a fibroid (myomectomy) may improve fertility outcomes, particularly when the uterine cavity is distorted.

How Do Fibroids Affect Pregnancy?

Most pregnancies complicated by fibroids progress normally. However, depending on their size and location, fibroids may be associated with an increased risk of:

Pain during pregnancy, sometimes caused by fibroid degeneration
Miscarriage or preterm birth
Abnormal fetal position (malpresentation)
Placental complications
Cesarean delivery or postpartum hemorrhage

Fibroids may grow during pregnancy, particularly early in pregnancy, although many remain stable. Some may decrease in size after delivery.

Having fibroids does not automatically mean you will need a cesarean delivery. Additional ultrasound monitoring or adjustments to delivery planning may be recommended depending on the characteristics of your fibroids.

Fibroids in Pregnancy (SMFM)

Fibroids During Perimenopause & Menopause

Uterine fibroids are influenced by reproductive hormones, particularly estrogen and progesterone. As hormone levels decline during menopause, fibroids often stop growing and may gradually shrink.

What Happens to Fibroids During Perimenopause?

During perimenopause, hormone levels fluctuate, and fibroids may continue to grow or contribute to heavy or irregular menstrual bleeding. However, not all abnormal bleeding during this transition is caused by fibroids, and additional evaluation may sometimes be necessary.

For patients approaching menopause, temporary medical management or observation may be reasonable, particularly if symptoms are manageable and there is a good chance they will improve after menopause.

What Happens to Fibroids After Menopause?

After menopause, fibroids generally stabilize or decrease in size, although they do not always disappear completely.

Heavy menstrual bleeding related to fibroids typically resolves once menstrual periods stop.
Pelvic pressure or urinary symptoms may improve as fibroids shrink, although larger fibroids can continue to cause symptoms.
Fibroids do not automatically require removal simply because they remain present after menopause.

Any vaginal bleeding after menopause should be evaluated, even if you have a history of uterine fibroids. New or enlarging uterine masses after menopause also warrant further assessment.