Uterine Fibroids: Symptoms, Causes & Treatment

What Are Uterine Fibroids?

Uterine fibroids (also called leiomyomas or myomas) are non-cancerous growths made of muscle and fibrous tissue that develop in or around the uterus. They range from tiny seedlings undetectable by the human eye to bulky masses that can distort and enlarge the uterus. A woman can have a single fibroid or multiple ones of varying sizes.

Uterine fibroids are the most common benign tumors in women of reproductive age. They develop from the smooth muscle cells of the uterine wall (myometrium) and can grow in different locations within or on the uterus. The exact cause of fibroids remains unknown, but they appear to be influenced by hormones, particularly estrogen and progesterone, which promote their growth during reproductive years.

These growths are remarkably common - research indicates that by age 50, approximately 70-80% of women will have developed at least one fibroid. However, many women are unaware they have fibroids because the majority cause no symptoms whatsoever. It's estimated that only 25-30% of women with fibroids experience symptoms significant enough to require medical attention or treatment.

Fibroids can vary dramatically in size, from microscopic to masses weighing several pounds. Some women have only one fibroid, while others may have multiple fibroids of different sizes scattered throughout the uterus. The location, size, and number of fibroids largely determine whether a woman will experience symptoms and what those symptoms might be.

Types of Fibroids Based on Location

Medical professionals classify fibroids based on where they grow in relation to the uterine wall. Understanding these different types is important because the location significantly influences symptoms, treatment options, and impact on fertility.

Intramural fibroids are the most common type, growing within the muscular wall of the uterus. As they enlarge, they can make the uterus feel larger than normal and cause heavy menstrual bleeding, pelvic pressure, and pain. These fibroids can grow large enough to distort both the inner cavity and outer surface of the uterus.

Subserosal fibroids develop on the outer surface of the uterus and grow outward. They typically don't affect menstrual flow but can cause pressure symptoms when large, pressing on the bladder (causing frequent urination) or rectum (causing constipation). Some subserosal fibroids develop a stalk (pedunculated fibroids) and can twist, causing sudden, severe pain.

Submucosal fibroids grow just beneath the inner lining of the uterus (endometrium) and protrude into the uterine cavity. Although less common (occurring in about 5% of cases), these often cause the most significant symptoms, particularly heavy and prolonged menstrual bleeding. They have the greatest impact on fertility because they can interfere with embryo implantation.

What Are the Symptoms of Uterine Fibroids?

The most common symptoms of uterine fibroids include heavy menstrual bleeding (menorrhagia), prolonged periods lasting more than a week, pelvic pressure or pain, frequent urination, difficulty emptying the bladder, constipation, backache, and leg pains. Some women also experience an enlarged abdomen that may be mistaken for weight gain or pregnancy.

Many women with fibroids have no symptoms at all and only discover them during routine pelvic examinations or imaging studies performed for other reasons. However, when symptoms do occur, they can significantly impact quality of life, work productivity, and daily activities. The type and severity of symptoms depend primarily on the location, size, and number of fibroids.

Heavy menstrual bleeding is the most common symptom that brings women to their healthcare provider. Women may experience periods with heavy flow requiring frequent pad or tampon changes (sometimes hourly), passage of blood clots, and periods lasting longer than seven days. This chronic blood loss can lead to iron-deficiency anemia, causing fatigue, weakness, and shortness of breath.

Pelvic pressure and pain are also common complaints. Large fibroids can create a sensation of fullness or heaviness in the lower abdomen. The pressure may be constant or intermittent and can worsen during menstruation. Some women describe feeling like they need to urinate or have a bowel movement even when they don't.

Bleeding Symptoms

Abnormal uterine bleeding associated with fibroids can manifest in several ways. Heavy menstrual bleeding (menorrhagia) is most characteristic, but women may also experience bleeding between periods, irregular cycles, and spotting. The bleeding pattern often depends on where the fibroid is located.

Submucosal fibroids, which grow into the uterine cavity, tend to cause the most significant bleeding problems. They can increase the surface area of the endometrium, disrupt normal uterine contractions that help control bleeding, and interfere with the clotting mechanisms. Even small submucosal fibroids can cause heavy bleeding disproportionate to their size.

The chronic heavy bleeding associated with fibroids often leads to iron-deficiency anemia. Symptoms of anemia include persistent fatigue, weakness, pale skin, shortness of breath with minimal exertion, and heart palpitations. If you're experiencing these symptoms along with heavy periods, it's important to have your hemoglobin levels checked.

Pressure Symptoms

As fibroids grow larger, they can press on surrounding organs and structures, causing various pressure-related symptoms. The specific symptoms depend on which organs are affected by the fibroid's location and size.

Bladder pressure from anterior (front-facing) fibroids can cause frequent urination, urgent need to urinate, and difficulty fully emptying the bladder. In severe cases, fibroids can cause urinary retention (inability to urinate) or recurrent urinary tract infections. Some women notice they need to wake multiple times at night to urinate (nocturia).

Bowel pressure from posterior (back-facing) fibroids pressing on the rectum can lead to constipation, bloating, and a sense of incomplete bowel movements. In rare cases, very large fibroids can cause bowel obstruction requiring emergency treatment.

Back and leg pain can occur when fibroids press on nerves in the pelvis. This may cause lower back pain, pain radiating down the legs (similar to sciatica), or general pelvic discomfort. The pain may be constant or may fluctuate with the menstrual cycle.

What Causes Uterine Fibroids?

The exact cause of uterine fibroids is unknown, but research suggests they develop from a combination of genetic factors, hormonal influences (particularly estrogen and progesterone), growth factors, and extracellular matrix abnormalities. Risk factors include family history, African ancestry, early menstruation, obesity, diet high in red meat, vitamin D deficiency, and nulliparity (never having given birth).

Despite being extremely common, the precise mechanisms that cause fibroids to develop remain incompletely understood. What researchers do know is that fibroids appear to arise from a single smooth muscle cell in the uterine wall that undergoes genetic changes, causing it to multiply rapidly and form a distinct mass. Multiple factors likely contribute to this process.

Hormones play a central role in fibroid growth. Estrogen and progesterone, the hormones that regulate the menstrual cycle and stimulate development of the uterine lining, appear to promote fibroid growth. Fibroids contain more estrogen and progesterone receptors than normal uterine muscle cells, making them particularly responsive to these hormones. This explains why fibroids develop during reproductive years, often grow during pregnancy (when hormone levels are high), and typically shrink after menopause.

Genetic factors also contribute significantly. Women with a mother or sister who has fibroids are about three times more likely to develop them. Specific gene mutations have been identified in fibroid tissue, particularly in genes involved in cell growth regulation. Research continues to uncover the complex genetic landscape that predisposes certain women to fibroid development.

Risk Factors

While any woman of reproductive age can develop fibroids, certain factors increase the likelihood:

• Age: Risk increases throughout reproductive years, peaking in the 40s and early 50s before menopause
• Family history: Having a first-degree relative with fibroids increases your risk approximately three-fold
• Ethnicity: Women of African descent develop fibroids 2-3 times more often than Caucasian women, typically at younger ages, with larger and more numerous fibroids, and more severe symptoms
• Obesity: Being overweight or obese increases risk, possibly due to higher circulating estrogen levels
• Diet: Studies suggest a diet high in red meat and ham may increase risk, while green vegetables appear protective
• Vitamin D deficiency: Low vitamin D levels have been associated with increased fibroid risk
• Early menarche: Starting menstruation before age 10 increases lifetime exposure to estrogen
• Nulliparity: Women who have never been pregnant have higher risk; each pregnancy appears to reduce risk

Protective Factors

Interestingly, certain factors appear to reduce the risk of developing fibroids or may help limit their growth. Pregnancy has a protective effect, with risk decreasing with each pregnancy. Breastfeeding, particularly for longer durations, also appears protective, likely due to the suppression of ovulation and reduced estrogen levels during lactation.

Hormonal contraceptives may also offer some protection. While the relationship is complex and older studies showed mixed results, more recent research suggests that current low-dose hormonal contraceptives don't promote fibroid growth and may even be protective. They're also effective at managing bleeding symptoms in women who already have fibroids.

How Are Uterine Fibroids Diagnosed?

Uterine fibroids are typically diagnosed through pelvic examination (where an enlarged or irregularly shaped uterus may be felt), confirmed by pelvic ultrasound (the first-line imaging test). MRI provides detailed mapping for surgical planning. Hysteroscopy allows direct visualization of the uterine cavity, while sonohysterography uses saline to better visualize submucosal fibroids.

The diagnostic process for uterine fibroids typically begins with a thorough medical history and physical examination. Your healthcare provider will ask about your symptoms, menstrual patterns, reproductive history, and any family history of fibroids. During the pelvic examination, the provider may detect an enlarged, irregularly shaped, or lumpy uterus that suggests the presence of fibroids.

However, physical examination alone cannot confirm fibroids or provide information about their exact location, size, and number. Imaging studies are essential for accurate diagnosis and treatment planning. The choice of imaging depends on the clinical situation and what information is needed.

Imaging Studies

Transvaginal ultrasound is typically the first imaging test ordered when fibroids are suspected. This painless procedure uses sound waves to create images of the uterus and can identify fibroids as small as a few millimeters. It's widely available, relatively inexpensive, and doesn't involve radiation exposure. Ultrasound can show the size, number, and general location of fibroids.

Magnetic Resonance Imaging (MRI) provides the most detailed images of fibroids and is particularly valuable for surgical planning. MRI can precisely map the location of multiple fibroids, determine their relationship to the uterine cavity, and help distinguish fibroids from other conditions like adenomyosis. It's often ordered before myomectomy or uterine artery embolization to ensure appropriate patient selection and procedural planning.

Sonohysterography (saline infusion sonography) involves injecting sterile saline into the uterine cavity during ultrasound. This expands the cavity and allows better visualization of submucosal fibroids that protrude into the uterine space. It's particularly useful when evaluating women with heavy bleeding or fertility concerns.

Hysteroscopy uses a thin, lighted telescope inserted through the cervix to directly visualize the inside of the uterus. It's the gold standard for evaluating the uterine cavity and can identify submucosal fibroids, polyps, and other abnormalities. In some cases, small submucosal fibroids can be removed during the same procedure (hysteroscopic myomectomy).

How Are Uterine Fibroids Treated?

Treatment for uterine fibroids depends on symptom severity, fibroid characteristics, age, and reproductive goals. Options include watchful waiting (for asymptomatic fibroids), medications (GnRH agonists/antagonists, tranexamic acid, hormonal contraceptives), minimally invasive procedures (uterine artery embolization, MRI-guided focused ultrasound), myomectomy (fibroid removal preserving the uterus), and hysterectomy (definitive treatment removing the uterus).

The approach to treating uterine fibroids has evolved significantly, with an increasing emphasis on individualized care that considers each woman's unique circumstances. Treatment isn't always necessary - many women with fibroids require no intervention at all. The decision to treat depends on several factors: the severity and impact of symptoms on quality of life, the woman's age and proximity to menopause, desire for future fertility, fibroid size, location, and number, and personal preferences regarding different treatment approaches.

For women with minimal or no symptoms, watchful waiting with regular monitoring is often the most appropriate approach. This involves periodic pelvic examinations and ultrasounds to track fibroid growth without active intervention. Since fibroids typically shrink after menopause, women approaching this transition may choose to manage symptoms conservatively until natural hormone decline leads to fibroid regression.

Medical Treatment

Medications can effectively manage fibroid symptoms and, in some cases, reduce fibroid size. While no medication permanently eliminates fibroids, medical therapy can provide significant relief and may be used alone or as a bridge to surgery.

GnRH agonists (gonadotropin-releasing hormone agonists like leuprolide) work by suppressing estrogen production, creating a temporary menopausal state. They can shrink fibroids by 30-50% and are often used before surgery to reduce fibroid size and blood loss. However, they cause menopausal side effects (hot flashes, vaginal dryness, bone loss) and can only be used for 3-6 months. Once stopped, fibroids typically regrow.

GnRH antagonists with add-back therapy (such as elagolix with estradiol/norethindrone) represent a newer approach. These medications suppress hormone production but include low-dose hormone "add-back" to minimize menopausal symptoms and protect bone density, allowing for longer-term use.

Tranexamic acid is a non-hormonal medication that reduces menstrual blood loss by helping blood clot more effectively. It's taken only during menstruation and can reduce heavy bleeding by 30-50%. It doesn't shrink fibroids but effectively manages bleeding symptoms.

Hormonal contraceptives (birth control pills, hormonal IUDs, progestin-only options) can help regulate menstrual cycles and reduce bleeding. The levonorgestrel-releasing intrauterine device (hormonal IUD) is particularly effective for heavy bleeding and can dramatically reduce menstrual flow. However, these methods don't shrink fibroids.

Iron supplementation is important for women with anemia from heavy bleeding. Treating iron deficiency can significantly improve energy levels and overall well-being while other treatments address the underlying cause.

Minimally Invasive Procedures

For women seeking treatment beyond medication but wanting to avoid major surgery, several minimally invasive options exist:

Uterine Artery Embolization (UAE) is performed by an interventional radiologist. Small particles are injected through a catheter into the arteries supplying the fibroids, blocking blood flow and causing the fibroids to shrink. UAE is done under sedation, requires no incisions, and most women go home the same day or next morning. Recovery takes about one to two weeks. UAE effectively reduces bleeding and bulk symptoms in 85-90% of patients. However, it's generally not recommended for women who want to become pregnant, though some women have successfully conceived after UAE.

MRI-guided focused ultrasound surgery (MRgFUS) uses high-intensity ultrasound waves, guided by MRI imaging, to heat and destroy fibroid tissue. It's completely non-invasive (no incisions or catheter insertion) and is performed as an outpatient procedure. The treatment works best for certain fibroid types and locations, and not all fibroids are suitable candidates. It's also not recommended for women planning pregnancy.

Radiofrequency ablation uses heat delivered through a needle to destroy fibroid tissue. This can be performed laparoscopically or through a transcervical approach. Recovery is typically quick, with most women returning to normal activities within a few days.

Surgical Treatment

Myomectomy is the surgical removal of fibroids while preserving the uterus. This is the preferred option for women who want to maintain fertility or keep their uterus for personal reasons. Myomectomy can be performed through several approaches depending on fibroid location:

• Hysteroscopic myomectomy: For submucosal fibroids, a telescope is inserted through the cervix to remove fibroids from inside the uterus. No incisions are needed, and recovery is typically quick (a few days).
• Laparoscopic myomectomy: Fibroids are removed through small incisions using a camera and specialized instruments. Suitable for subserosal and some intramural fibroids. Faster recovery than open surgery.
• Abdominal myomectomy: An open surgery through an abdominal incision, necessary for very large fibroids or when multiple fibroids need removal. Longer recovery (4-6 weeks) but allows removal of fibroids that can't be accessed by other methods.

A key consideration with myomectomy is that fibroids can recur. Studies show that within 5-10 years, 15-30% of women who undergo myomectomy will need additional treatment for new or recurring fibroids.

Hysterectomy (surgical removal of the uterus) is the only treatment that guarantees fibroids won't return. It may be recommended for women with severe symptoms who don't respond to other treatments, don't want future pregnancies, and want a definitive solution. Hysterectomy can be performed vaginally, laparoscopically, or through an abdominal incision. The ovaries may or may not be removed depending on the clinical situation and patient preferences. While hysterectomy eliminates fibroids permanently, it's major surgery with a longer recovery period and ends the possibility of pregnancy.

Can You Get Pregnant with Uterine Fibroids?

Many women with fibroids conceive naturally and have healthy pregnancies. However, fibroids can affect fertility depending on their location - submucosal fibroids have the greatest impact as they can interfere with embryo implantation. Large intramural fibroids may also affect fertility. Subserosal fibroids typically don't impact conception. Women having difficulty conceiving should consult a fertility specialist.

The relationship between fibroids and fertility is complex and depends significantly on fibroid characteristics, particularly location. While many women with fibroids have no difficulty conceiving, fibroids are found in approximately 5-10% of women with infertility. Understanding how different types of fibroids affect reproduction can help guide treatment decisions.

Submucosal fibroids have the clearest impact on fertility. These fibroids grow into the uterine cavity and can interfere with several reproductive processes: they may prevent sperm from reaching the egg, disrupt embryo implantation by distorting the endometrial lining, and increase the risk of miscarriage. Studies consistently show that removing submucosal fibroids improves pregnancy rates in women undergoing fertility treatment.

Intramural fibroids (those within the uterine wall) have a more variable effect on fertility. Small intramural fibroids that don't distort the uterine cavity may have minimal impact. However, larger intramural fibroids, particularly those greater than 4-5 cm or those that indent the uterine cavity, may reduce fertility and increase miscarriage risk. The decision to remove intramural fibroids before attempting pregnancy requires careful consideration of fibroid characteristics and individual circumstances.

Subserosal fibroids (growing on the outer surface of the uterus) generally don't affect fertility unless they're very large or positioned in a way that could block the fallopian tubes. These fibroids typically don't require treatment before attempting pregnancy.

Fibroids and Pregnancy

Women who become pregnant with fibroids may face some increased risks, though many have uncomplicated pregnancies. During pregnancy, fibroids may grow due to increased estrogen levels, remain the same size, or occasionally decrease. Pain can occur if a fibroid outgrows its blood supply and begins to degenerate (known as "red degeneration"), which is managed with rest and pain medication.

Potential pregnancy complications associated with fibroids include:

• Increased risk of miscarriage, particularly with submucosal fibroids
• Preterm labor and premature delivery
• Abnormal fetal position (breech presentation)
• Placental problems, including placental abruption
• Higher likelihood of cesarean delivery
• Postpartum hemorrhage

Women with fibroids who are pregnant or planning pregnancy should receive care from providers experienced in managing fibroids during pregnancy. Close monitoring throughout pregnancy can help identify and address any complications early.

When Should You See a Doctor?

See a doctor if you experience heavy menstrual bleeding soaking through a pad or tampon every hour, periods lasting longer than 7 days, severe pelvic pain, difficulty urinating or frequent urination, constipation, a noticeably enlarged abdomen, or signs of anemia (fatigue, weakness, shortness of breath). Seek emergency care for severe pelvic pain with fever, heavy bleeding with dizziness, or inability to urinate.

Many women normalize heavy periods or assume their symptoms are just part of normal menstruation. However, certain signs warrant medical evaluation, as effective treatments exist that can dramatically improve quality of life.

Schedule an appointment with your healthcare provider if you experience:

• Menstrual periods that require changing pads or tampons more than every two hours
• Passing large blood clots during your period
• Periods lasting more than seven days
• Bleeding between periods
• Chronic pelvic pain or pressure that interferes with daily activities
• Needing to urinate frequently or difficulty emptying your bladder
• Persistent constipation not relieved by diet changes
• Unexplained enlargement of your abdomen
• Persistent fatigue, weakness, or shortness of breath (signs of anemia)

Can Lifestyle Changes Help Manage Fibroids?

While lifestyle changes cannot cure or shrink fibroids, certain habits may help manage symptoms and possibly reduce risk. Maintaining a healthy weight, eating plenty of fruits and vegetables (especially green leafy vegetables), limiting red meat and alcohol, getting adequate vitamin D, and regular exercise may be beneficial. These strategies are best used alongside medical treatment, not as a replacement.

Research into lifestyle factors and fibroids is ongoing, and while no lifestyle modification has been proven to definitively prevent or treat fibroids, some evidence suggests certain habits may be helpful as part of an overall management strategy.

Diet: Several studies have found associations between diet and fibroid risk or symptoms. Diets high in fruits and vegetables, particularly green leafy vegetables and citrus fruits, appear to be associated with lower fibroid risk. Conversely, high consumption of red meat and ham has been linked to increased risk. A Mediterranean-style diet rich in vegetables, fruits, legumes, and fish may be beneficial. Some research suggests dairy consumption may be protective, possibly due to its calcium and vitamin D content.

Weight management: Obesity is a known risk factor for fibroids, likely due to increased estrogen production in fat tissue. Maintaining a healthy weight through balanced nutrition and regular physical activity may help reduce risk and potentially slow fibroid growth. Even modest weight loss can have health benefits.

Exercise: Regular physical activity is associated with lower fibroid risk in some studies. Exercise helps maintain healthy weight, may influence hormone levels, and generally supports overall health. Aim for at least 150 minutes of moderate-intensity aerobic activity per week.

Vitamin D: Low vitamin D levels have been associated with increased fibroid risk and larger fibroid size. While more research is needed, ensuring adequate vitamin D through sun exposure, diet, or supplements (after consulting with your healthcare provider) may be reasonable.

Managing symptoms: For symptom relief, applying heat (heating pad or warm bath) can help with pelvic pain and cramping. Over-the-counter pain relievers like ibuprofen can manage pain and may slightly reduce menstrual bleeding. If you have heavy periods, iron-rich foods or supplements can help prevent or treat anemia.