Uterine fibroids are noncancerous growths that develop in or on the uterus. They are also called leiomyomas or myomas. Fibroids are very common during the reproductive years and can range from tiny growths that cause no symptoms to large masses that lead to heavy periods, pelvic pressure, pain, urinary symptoms, or fertility problems. If you are researching fibroids as a partner, future parent, or patient, the key point is this: fibroids are usually benign, but their size, number, and location can matter a lot for symptoms, pregnancy, and reproductive planning.
Because SWMR readers are often focused on fertility and conception, it is worth knowing that uterine fibroids are not a male health condition, but they can still affect a couple’s path to pregnancy. Some fibroids do not interfere with fertility at all, while others can distort the uterine cavity, make implantation harder, increase miscarriage risk, or complicate pregnancy.
Key takeaways
- Uterine fibroids are benign smooth muscle tumors of the uterus and are very common.
- Many fibroids cause no symptoms and are found incidentally on a pelvic exam or ultrasound.
- When symptoms happen, they often include heavy menstrual bleeding, pelvic pressure, pain, urinary frequency, constipation, or an enlarged abdomen.
- The effect on fertility depends heavily on where the fibroid is located, not just how large it is.
- Submucosal fibroids and fibroids that distort the uterine cavity are the most likely to affect implantation and pregnancy outcomes.
- Diagnosis usually involves a pelvic exam and imaging, especially pelvic ultrasound.
- Treatment ranges from watchful waiting to medication, minimally invasive procedures, or surgery such as myomectomy.
- Anyone with severe bleeding, anemia symptoms, rapidly worsening pain, fertility concerns, or pregnancy-related symptoms should seek medical care.
What are uterine fibroids?
Uterine fibroids are growths made of smooth muscle cells and fibrous connective tissue that arise from the wall of the uterus. They are not the same as cancer, and the overwhelming majority do not become cancerous. Fibroids can occur as a single growth or as multiple growths, and they vary widely in size.
Some are as small as a seed and can only be seen on imaging. Others can become large enough to enlarge the uterus and press on nearby organs, including the bladder or bowel. Fibroids are influenced by reproductive hormones, especially estrogen and progesterone, which helps explain why they often grow during the reproductive years and may shrink after menopause.
People often discover fibroids after searching for answers to symptoms like:
- Why is my period suddenly so heavy?
- Why do I feel pelvic pressure or bloating?
- Can fibroids cause infertility or miscarriage?
- What does a fibroid on ultrasound mean?
Those are all reasonable questions. The right answer depends on the growth’s size, number, and exact location in the uterus.
Types of uterine fibroids
Doctors classify fibroids based on where they grow. This is one of the most important parts of understanding symptoms and fertility effects.
| Type of fibroid | Where it grows | Common effects | Possible fertility impact |
|---|---|---|---|
| Intramural | Within the muscular wall of the uterus | Heavy bleeding, pressure, enlarged uterus | May affect fertility if large or if it distorts the uterine cavity |
| Submucosal | Just beneath the uterine lining, bulging into the cavity | Heavy bleeding, infertility, miscarriage risk | Most likely type to interfere with implantation and pregnancy |
| Subserosal | On the outer surface of the uterus | Pressure, pelvic fullness, urinary or bowel symptoms | Usually less effect on fertility unless very large |
| Pedunculated | Attached by a stalk, either inside or outside the uterus | Can cause pain if twisted | Depends on size and location |
| Cervical | In the cervix | Pressure, bleeding, pain, possible labor or delivery issues | Can affect sperm passage or fertility in some cases |
Among these, submucosal fibroids are the ones most strongly linked to reduced fertility because they can change the shape of the uterine cavity where an embryo would implant.
Why uterine fibroids matter
Fibroids matter because they can affect day-to-day quality of life, reproductive health, and medical decision-making. For some people, they are merely an ultrasound finding. For others, they lead to severe menstrual bleeding, iron deficiency anemia, chronic pelvic symptoms, difficulty getting pregnant, or pregnancy complications.
From a fertility perspective, fibroids may matter in several ways:
- They may distort the uterine cavity, making implantation harder.
- They may change blood flow or the architecture of the uterus.
- They can be associated with miscarriage in some situations, especially if submucosal.
- They may complicate fertility treatment planning, including IUI or IVF.
- During pregnancy, they may increase the chance of pain, bleeding, malpresentation, or cesarean delivery in some cases.
For male partners, fibroids can become part of the couple’s fertility workup. Even if semen quality is normal, the uterine environment still matters for conception and carry-to-term success.
Symptoms of uterine fibroids
Many uterine fibroids cause no symptoms. When symptoms do occur, they depend on location, size, and number rather than the diagnosis alone.
Common fibroid symptoms
- Heavy menstrual bleeding
- Periods that last longer than usual
- Passing blood clots during menstruation
- Pelvic pressure or fullness
- Pelvic pain or cramps
- Lower back pain
- Frequent urination or trouble fully emptying the bladder
- Constipation or rectal pressure
- Pain during sex in some cases
- Abdominal enlargement or “bloating”
- Difficulty getting pregnant
- Repeated pregnancy loss in some cases
Symptoms linked to heavy bleeding
Heavy bleeding from fibroids can lead to iron deficiency and anemia. That can cause:
- Fatigue
- Weakness
- Shortness of breath
- Dizziness
- Pale skin
- Reduced exercise tolerance
When fibroids hurt
Fibroids are not always painful, but pain can happen. A fibroid may outgrow its blood supply, undergo degeneration, or cause pressure on nearby structures. Pedunculated fibroids can occasionally twist, which may cause sudden severe pain and needs urgent evaluation.
Causes and risk factors
The exact cause of uterine fibroids is not fully understood. They likely develop from a single smooth muscle cell in the uterus that begins to grow abnormally under hormonal and genetic influences.
What may contribute to fibroid growth
- Hormones: Estrogen and progesterone appear to promote fibroid growth.
- Genetics: Fibroids often run in families.
- Age: They are most common during reproductive years.
- Race: Fibroids are more common, may occur earlier, and may be more severe in Black women.
- Obesity: Higher body weight is associated with increased risk.
- Early menstruation: Earlier menarche may be associated with higher risk.
- Diet and lifestyle factors: Associations have been studied, but they do not fully explain who develops fibroids.
What does not cause fibroids?
Fibroids are not caused by stress alone, sexual activity, an abortion, or a sexually transmitted infection. They also are not a sign that someone has uterine cancer.
What’s normal vs what’s not?
There is no single “normal fibroid size” because a fibroid does not have to be large to matter. A small submucosal fibroid can affect bleeding or fertility more than a larger subserosal fibroid.
| Situation | Often considered less concerning | More likely to need medical attention |
|---|---|---|
| Symptoms | No symptoms or mild symptoms | Heavy bleeding, severe pain, pressure, anemia, infertility |
| Location | Small fibroid on outer uterine surface | Fibroid that distorts the uterine cavity |
| Bleeding | Periods similar to usual cycle pattern | Soaking pads or tampons quickly, passing large clots, prolonged bleeding |
| Fertility | No cavity distortion and no pregnancy history concerns | Difficulty conceiving, implantation failure, recurrent miscarriage |
| Pregnancy | Stable, asymptomatic fibroids | Severe pain, bleeding, placental or fetal position concerns |
What matters most is not whether fibroids exist, but how they are behaving clinically. A symptom-free person with small fibroids may only need observation. Someone with infertility or major bleeding may need imaging, lab tests, or treatment.
How uterine fibroids are diagnosed
Fibroids are often detected during evaluation for heavy periods, pelvic pain, infertility, or an enlarged uterus. Some are first found incidentally during pregnancy imaging or a routine pelvic exam.
Common tests used to diagnose fibroids
- Medical history: Symptoms such as bleeding, pressure, pain, urinary frequency, and fertility history help guide the workup.
- Pelvic exam: A clinician may feel an enlarged or irregularly shaped uterus.
- Pelvic ultrasound: Usually the first imaging test. It can show fibroid size, number, and approximate location.
- Transvaginal ultrasound: Often gives better detail than abdominal ultrasound.
- Saline infusion sonography: Saline is placed into the uterus during ultrasound to better assess cavity distortion.
- Hysteroscopy: A thin camera is inserted through the cervix to look inside the uterus, especially helpful for submucosal fibroids.
- MRI: Used in selected cases for surgical planning, large fibroids, unclear anatomy, or before some procedures.
- Blood tests: These may be used to check for anemia or other causes of abnormal bleeding.
How fibroids show up on imaging
A report may mention:
- Size in centimeters
- Number of fibroids
- Location, such as intramural or submucosal
- Whether the endometrial cavity is distorted
- Whether there is degeneration or blood flow changes
If fertility is the concern, one of the most important questions is whether the fibroid changes the shape of the uterine cavity.
Uterine fibroids and fertility
Fibroids do not always cause infertility. Many people with fibroids conceive naturally and have healthy pregnancies. Still, certain fibroids can reduce fertility or make treatment less successful.
How fibroids may affect conception
- They may interfere with embryo implantation.
- They may block or distort the uterine cavity.
- They may alter uterine contractions or local blood flow.
- Large fibroids near the fallopian tube openings may affect sperm or egg transport.
- Some can raise the risk of miscarriage, depending on type and location.
Which fibroids are most likely to reduce fertility?
Submucosal fibroids are the clearest concern because they protrude into the uterine cavity. Intramural fibroids can also matter if they are large or distort the cavity. Small subserosal fibroids on the outside of the uterus are usually less likely to interfere with conception.
Fibroids and IVF
If a couple is planning IVF, the reproductive specialist may pay close attention to fibroids that:
- Distort the cavity
- Are submucosal
- Are large intramural fibroids near the endometrium
- Have previously been associated with implantation failure or miscarriage
In some cases, removing a cavity-distorting fibroid before IVF may improve outcomes. The decision is individualized and depends on imaging findings, age, ovarian reserve, symptoms, and time-sensitive fertility goals.
Why this matters for couples
When a couple is trying to conceive, the fertility picture is shared. One partner may be evaluating sperm count, motility, or morphology, while the other is being assessed for ovulation, tubal patency, or uterine factors such as fibroids. Good fertility care looks at both sides together.
Fibroids during pregnancy
Many people with fibroids have uncomplicated pregnancies. However, fibroids can sometimes contribute to symptoms or obstetric complications depending on their size and location.
Possible pregnancy-related issues associated with fibroids
- Pain from fibroid degeneration
- Bleeding
- Placental problems in some cases
- Malpresentation, such as breech position
- Preterm labor risk in selected cases
- Labor obstruction if a fibroid blocks the birth canal
- Increased likelihood of cesarean delivery
It is important to keep the risk in perspective. Not every fibroid causes pregnancy problems, and many are simply monitored. If someone is pregnant and has severe pain, bleeding, or signs of preterm labor, they should contact their obstetric clinician promptly.
Treatment options for uterine fibroids
Treatment depends on symptoms, age, reproductive goals, fibroid size and location, and whether pregnancy is desired now or in the future. There is no single best treatment for everyone.
1. Watchful waiting
If fibroids are small and not causing symptoms, a clinician may recommend observation. This often includes:
- Monitoring symptoms over time
- Repeat pelvic exam or ultrasound if needed
- Reassessment if bleeding, pain, or fertility concerns develop
2. Medications
Medication may help manage bleeding, pain, or fibroid size, but it does not permanently remove fibroids.
- NSAIDs may reduce menstrual pain.
- Hormonal birth control may help control bleeding in some patients.
- Levonorgestrel-releasing IUD can reduce heavy bleeding in selected cases, depending on uterine anatomy.
- GnRH agonists or antagonists may shrink fibroids temporarily and reduce bleeding, often used before surgery or for short-term management.
- Tranexamic acid may reduce heavy menstrual bleeding during periods.
Medication choice depends on symptoms and fertility goals. Some hormonal options are not ideal if immediate conception is the goal.
3. Myomectomy
Myomectomy is surgery to remove fibroids while preserving the uterus. It is often the preferred surgical option for people who want future pregnancy, especially when fibroids are thought to affect fertility.
Types of myomectomy include:
- Hysteroscopic myomectomy: For submucosal fibroids accessible through the cervix
- Laparoscopic or robotic myomectomy: Minimally invasive abdominal approaches
- Open abdominal myomectomy: Used for larger or numerous fibroids in some cases
Even after successful myomectomy, fibroids can recur over time.
4. Uterine artery embolization
Uterine artery embolization (UAE) blocks blood flow to fibroids so they shrink. It can improve bleeding and bulk symptoms, but it is not always the preferred option for those actively planning pregnancy because its effects on fertility and future pregnancy are more complex than with myomectomy.
5. MRI-guided focused ultrasound
This is a noninvasive treatment that uses focused ultrasound energy to heat and destroy fibroid tissue in selected cases. It is not appropriate for everyone, and access may be limited.
6. Endometrial ablation
This treats the uterine lining to reduce bleeding, but it is not a fertility-preserving treatment and is generally not suitable for people who want future pregnancy.
7. Hysterectomy
Hysterectomy removes the uterus and is the only definitive cure for fibroids. It ends the possibility of pregnancy and is usually considered for severe symptoms when fertility preservation is not desired.
Treatment comparison
| Treatment | Can preserve fertility? | Main benefit | Main limitation |
|---|---|---|---|
| Watchful waiting | Yes | Avoids unnecessary treatment | Does not relieve significant symptoms |
| Medications | Sometimes | Can reduce bleeding or pain | Often temporary control, not removal |
| Myomectomy | Often yes | Removes fibroids while keeping uterus | Surgery risks and recurrence possible |
| Uterine artery embolization | Uncertain for some fertility goals | Less invasive than major surgery | Not ideal for every future-pregnancy plan |
| Focused ultrasound | Potentially | Noninvasive in selected patients | Availability and suitability vary |
| Hysterectomy | No | Definitive treatment | Ends fertility |
Lifestyle and self-management
Lifestyle changes do not reliably eliminate fibroids, but they can support overall health and help manage symptoms or treatment recovery.
Helpful self-management strategies
- Track symptoms: Note bleeding days, clotting, pain, urinary symptoms, and cycle changes.
- Address iron deficiency: If heavy bleeding is present, ask about testing for anemia and iron deficiency.
- Use pain relief appropriately: Over-the-counter pain medicines may help, but speak with a clinician if symptoms are frequent or severe.
- Support general metabolic health: A balanced diet, regular exercise, and healthy body weight may support overall reproductive health.
- Prioritize fertility timing: If pregnancy is a goal, avoid delaying specialist evaluation when fibroids may be affecting conception.
Can fibroids be shrunk naturally?
There is no proven natural remedy that reliably shrinks uterine fibroids. Be cautious with supplements, “hormone balancing” products, or online detox plans that promise to dissolve fibroids. Some may be ineffective, expensive, or unsafe. If symptoms are significant, medical evaluation matters.
Common myths and misconceptions
Myth: Fibroids are cancer.
False. Fibroids are benign growths. Rare uterine sarcomas are a separate condition and cannot usually be distinguished by symptoms alone, but fibroids themselves are not considered cancerous tumors.
Myth: Every fibroid causes infertility.
False. Many fibroids do not affect fertility at all. The main issue is location, especially whether the uterine cavity is distorted.
Myth: Large fibroids are always worse than small ones.
Not necessarily. A small fibroid inside the uterine cavity can matter more for fertility than a larger fibroid on the outside of the uterus.
Myth: Hysterectomy is the only treatment.
False. Many patients can be managed with observation, medication, myomectomy, or other uterus-sparing options depending on goals and symptoms.
Myth: Pregnancy always makes fibroids dangerous.
False. Many pregnancies with fibroids go well. Some fibroids cause no pregnancy problems, while others need closer monitoring.
Questions to ask your doctor
If you or your partner has been told there are uterine fibroids, these questions can help make the visit more useful:
- How many fibroids are there, and what type are they?
- Do any of them distort the uterine cavity?
- Could these fibroids explain the bleeding, pain, or fertility problems?
- Do I need additional imaging such as saline sonography, hysteroscopy, or MRI?
- If pregnancy is a goal, should we consider treatment before trying to conceive or before IVF?
- What are the pros and cons of myomectomy versus observation in my case?
- Could I be anemic from heavy bleeding, and should I have iron studies checked?
- What symptoms would require urgent evaluation?
- If surgery is recommended, how might it affect future pregnancy or delivery?
Frequently asked questions
Are uterine fibroids cancerous?
No. Uterine fibroids are benign growths. They are not the same as uterine cancer, and most do not become cancerous.
Can uterine fibroids cause infertility?
They can, but not always. Fibroids are most likely to affect fertility when they distort the uterine cavity, especially submucosal fibroids.
Do fibroids always need treatment?
No. If fibroids are not causing symptoms and are not affecting fertility or pregnancy planning, they may only need monitoring.
Can fibroids cause heavy periods?
Yes. Heavy menstrual bleeding is one of the most common symptoms of uterine fibroids, particularly submucosal and some intramural fibroids.
Can fibroids cause miscarriage?
Some fibroids, especially those that distort the uterine cavity, may increase miscarriage risk. The relationship depends on the type and location of the fibroid.
Can you get pregnant with fibroids?
Yes. Many people with fibroids conceive naturally. Whether fibroids interfere depends on their size, number, and location.
What is the best test for uterine fibroids?
Pelvic ultrasound is usually the first and most common test. Additional tests like saline infusion sonography, hysteroscopy, or MRI may be used for more detail.
Will fibroids go away after menopause?
Fibroids often shrink after menopause because hormone levels fall, but they do not always disappear completely.
What’s the difference between fibroids and ovarian cysts?
Fibroids grow from the uterus, while ovarian cysts arise from the ovary. They are different conditions with different causes and management.
Can men be affected by uterine fibroids?
Men do not develop uterine fibroids, but fibroids can affect a couple’s fertility journey, pregnancy planning, treatment timing, and emotional stress around conception.
When to seek medical care
Speak with a clinician if there is:
- Heavy or prolonged menstrual bleeding
- Symptoms of anemia, such as fatigue or dizziness
- Pelvic pain, pressure, or rapidly worsening abdominal enlargement
- Trouble urinating or severe constipation from pelvic pressure
- Difficulty conceiving or repeated miscarriage
- Known fibroids plus plans for pregnancy or IVF
- Sudden severe pelvic pain
- Pregnancy with fibroids and new pain or bleeding
If bleeding is severe, pain is sudden and intense, or there are signs of significant weakness, fainting, or shortness of breath, urgent medical attention is appropriate.
The bottom line
Uterine fibroids are common, benign growths of the uterus. They range from harmless incidental findings to clinically important causes of heavy bleeding, pain, pressure, and fertility challenges. The single most important detail is often where the fibroid is located. For anyone trying to conceive, especially couples navigating infertility, fibroids are a uterine factor worth understanding clearly and evaluating thoughtfully.
The good news is that many fibroids do not need treatment, and for those that do, there are several medical and surgical options. If fibroids are part of your fertility story, the best next step is not guessing based on size alone, but getting a clear assessment of anatomy, symptoms, and reproductive goals.
References
- American College of Obstetricians and Gynecologists (ACOG). Uterine Fibroids.
- National Institute for Health and Care Excellence (NICE). Heavy Menstrual Bleeding: Assessment and Management.
- Office on Women’s Health, U.S. Department of Health and Human Services. Uterine Fibroids Fact Sheet.
- Mayo Clinic. Uterine Fibroids.
- Merck Manual Professional Edition. Uterine Leiomyomas.
- Practice Committee of the American Society for Reproductive Medicine (ASRM). Guidance on myomas and reproductive function.
- National Library of Medicine, MedlinePlus. Uterine Fibroids.
