An enlarged uterus means your womb (where babies grow) gets bigger than normal. It's normal for your uterus to grow larger (enlarge) with hormonal changes, such as higher estrogen levels.
But an enlarged uterus can be a symptom of fibroids (leiomyomas), thickening of the uterus (due to adenomyosis), or cancer. Early diagnosis can help you get the best medical care. Find out the causes, symptoms, and treatments for an enlarged uterus.
What Causes an Enlarged Uterus?
Higher amounts of the reproductive hormone estrogen can change the structure of your uterus. Because your womb is a muscular organ, it can grow larger than normal.
Here are some conditions that can cause an enlarged uterus.
Hormonal changes
As your hormone levels change, especially estrogen, the size of your uterus can, too. Without progesterone, higher estrogen levels can thicken the wall of your uterus.
Over time, this can enlarge your uterus. This condition is called endometrial hyperplasia. With endometrial hyperplasia, you may:
- Use medicine that acts like estrogen (tamoxifen to treat cancer)
- Take estrogen-only hormone therapy
- Have irregular periods linked to polycystic ovarian syndrome (PCOS) or infertility
- Have a higher BMI
As the lining of your uterus gets thicker, rarely, the changes can lead to endometrial cancer. More often, hormone changes cause benign (noncancerous) growths called uterine fibroids.
Uterine fibroids
Fibroids, also called leiomyomas, are common noncancerous lumps in your uterus. You can have a single fibroid or many. About three-quarters of women get fibroids by age 50. But you have a lower fibroid risk if you've given birth.
Some fibroids are small, pea-sized. But others can grow larger, like a melon. Fibroids can grow when your estrogen levels are higher. They can show up during pregnancy and shrink again during menopause.
Ovarian cysts
Ovarian cysts are fluid-filled pockets that form on your ovaries. Most go away on their own without causing any problems. But you can have symptoms if a cyst grows large, bursts, or twists.
The symptoms are usually pelvic pain, menstrual cycle changes, or bloating. Sometimes, your uterus can feel larger or more uncomfortable, too.
Pregnancy or perimenopause
Your womb grows larger during pregnancy — from the size of a pear to the size of a watermelon. It's normal for your uterus to change sizes during and after pregnancy. That's because your womb grows to support your baby.
But if you had a fibroid already, pregnancy hormones can cause your fibroid to grow bigger. After delivery, your hormone levels drop, and your fibroid usually shrinks back to its prepregnancy size. This may take a few weeks as your body naturally heals.
Around menopause (perimenopause), higher estrogen levels can cause your uterus to temporarily grow. Your uterus may get bigger, especially if you have uterine fibroids. But the fibroids shrink when your hormone levels drop during menopause.
Adenomyosis
Adenomyosis causes the lining of your uterus (endometrium) to grow into the muscle layer of the uterus. Although the exact cause is unknown, higher estrogen levels may lead to this condition. As the lining moves into the outer wall of your uterus, it gets thicker.
Your uterus can grow two to three times its original size. This condition can happen at any time, but it's more common between the ages of 35 and 50. Adenomyosis usually affects the whole uterus. But if it's in one spot, it's called an adenomyoma.
Uterine cancer
Different kinds of uterine (endometrial) cancer can grow in the lining of your uterus. But type 1 tumors depend on estrogen to grow. This slower-growing tumor is more common after menopause.
Usually, abnormal bleeding is the first sign. But later-stage uterine cancer can enlarge your uterus. About 69,120 people are expected to get uterine cancer in the U.S. this year.
What Are the Symptoms of an Enlarged Uterus?
Not everyone gets enlarged uterus symptoms. The symptoms can depend on what's causing your enlarged uterus.
With an enlarged uterus, you may have:
- Unusual vaginal bleeding after menopause or between your periods
- Heavy, painful, or long-lasting periods
- Bleeding between periods or passing of blood clots
- Bloating ("adenomyosis belly") or a feeling of fullness in your lower belly
- A frequent need to pee
- Lower back pain
- Pelvic pain or pain during sex
- Constipation
- Trouble getting pregnant
- Lump in your vagina
If you have any unusual spotting, see your OB/GYN. They can help you find out what's causing the abnormal bleeding.
Risk for uterine fibroids and adenomyosis
Many enlarged uterus symptoms can look like other medical conditions. But knowing your risk can help you get treatment early.
You may have a higher risk for uterine fibroids or adenomyosis if you:
- Are over 30 years old
- Have a high BMI or are 20% over your target weight
- Had your first period before you were 12 years old
- Have shorter periods (exposed to more estrogen)
You also have a higher fibroid risk if you:
- Have a family history of fibroids
- Have vitamin D deficiency
- Have high blood pressure
- Are Black
Your risk is higher for adenomyosis if you have:
- Exposure to hormones such as progesterone, prolactin, or follicle-stimulating hormone (FSH)
- A history of uterine surgery, such as a C-section
Risk for uterine cancer
Unlike fibroid and adenomyosis, your uterine cancer risk goes up if you've never had children.
Higher estrogen levels can raise your cancer risk if you:
- Get hormone replacement therapy without progesterone
- Get cancer treatment, such as tamoxifen or pelvic radiation
- Get your period before 12 years old or late menopause
- Have a family history of uterine cancer or inherit a condition such as Lynch syndrome
- Are of older age
- Have obesity or type 2 diabetes
- Have polycystic ovarian syndrome (PCOS) or endometrial hyperplasia
- Had eye cancer (retinoblastoma) as a child
How Is an Enlarged Uterus Diagnosed?
Your OB/GYN may first notice your enlarged uterus during a routine pelvic exam. Your uterus may feel larger, softer, or tender.
"To figure out the underlying cause, a full medical workup is important," says Kecia Gaither, MD, MPH, an OB/GYN at NYC Health + Hospitals/Lincoln in New York. "Complete history, physical exam, and pelvic ultrasound are ordered."
Your doctor may order tests, including imaging tests. These tests include:
Ultrasound. This test uses sound waves to create pictures of your uterus. It checks for fibroids or thickening in the uterine wall.
Transvaginal ultrasound. A small ultrasound probe is inserted into your womb. This scan can check for abnormal tissue growth in your uterus.
MRI. An MRI can give a clear image of your uterus. The scan can show the size, location, and number of fibroids. This test usually diagnoses adenomyosis. MRI can also stage uterine cancer.
Hysteroscopy. A thin, flexible tube with a camera is inserted through your vagina. Your doctor looks directly inside your uterus for any unusual uterine growths.
Sonohysterography. In this ultrasound scan, saline is injected into the uterus to get a clearer view inside of your uterus.
Hysterosalpingography (HSG). This is an X-ray test using contrast material, which can check for fibroids.
Dilation and curettage (D&C). A spoon-shaped device is inserted into your vagina, which gently scrapes out parts of your uterine lining. Your doctor then looks at the tissue sample under a microscope for cancer cells.
Laparoscopy. It's a surgery in which your doctor inserts a camera to get a closer look at your uterus and other organs. This is done using a small cut made in your belly.
Your doctor may also do blood tests, such as a "complete blood count (CBC), metabolic panel, and pregnancy testing," she says. Knowing the cause of your enlarged uterus can help you decide on the best treatment.
How Do You Treat an Enlarged Uterus?
Your treatment depends on the cause of your enlarged uterus. Many people don't have symptoms or may have mild symptoms that may not need treatment right away.
Your doctor may suggest regular checkups to track your progress. Or you may get imaging tests to keep an eye on things. In fact, only about 10 to 20 out of 100 fibroids need treatment.
Medications
Your doctor may prescribe medication to help with your symptoms.
Pain-relievers. Over-the-counter (OTC) medicines such as acetaminophen or ibuprofen can soothe your cramps. Pain medication may also help ease discomfort from fibroids or adenomyosis.
Iron supplements. Iron supplements can help prevent anemia if your heavy bleeding causes low iron.
Hormonal birth control. Oral contraceptive pills, intrauterine devices (IUDs) with progesterone, or shots can help lessen heavy bleeding. Hormones can also help ease painful periods from fibroids or adenomyosis.
Hormone therapies. Gonadotropin-releasing hormone (GnRH) agonists, such as elagolix (Orilissa), stop your ovaries from making hormones. It can stop your menstrual bleeding to treat adenomyosis and fibroids. The therapy can shrink fibroids and make them easier to remove.
Tranexamic acid (Lysteda). This medicine helps your blood clot to reduce heavy bleeding.
Danazol. This man-made steroid can lower FSH levels to shrink abnormal uterine tissue. It can also lighten your menstrual bleeding.
Minimally invasive procedures
Many minimally invasive options can help shrink or destroy fibroids without major surgery. But your uterus is still intact, and your condition can come back.
Focused ultrasound surgery (FUS). Inside an MRI machine, sound waves heat and destroy fibroid tissue without giving you any cuts (incisions).
Uterine artery embolization (UAE). Tiny particles are injected into the arteries (blood vessels) that supply blood to your fibroid. They cut off the blood supply and shrink your fibroid or adenomyosis tissue.
Endometrial ablation. In endometrial ablation, heat, cold, or radio waves are used to remove your uterine lining. This can reduce heavy bleeding from fibroids or adenomyosis. But it isn't suggested if you're planning on getting pregnant in the future.
Surgical options
With serious symptoms or if other treatments aren't working, your doctor may suggest surgery.
Myomectomy. This removes larger, deeper, or multiple fibroids (myomas). You keep your uterus, but the scar tissue can lower your chance for future pregnancy.
Your surgeon can insert tools through a small cut in your belly button (laparoscopic), vagina (hysteroscopic), or belly (laparotomy). A robotic system can also be used for precision.
Hysterectomy. This removes your enlarged uterus completely. It's a permanent solution often used for cancer. Fibroids and adenomyosis can't come back either. But it also means you won't be able to get pregnant.
Adenomyomectomy. This removes adenomyosis tissue from your uterine wall. Like a myomectomy, you can try for a future pregnancy after this.
Can You Reduce an Enlarged Uterus Naturally?
There's no specific way to naturally shrink your enlarged uterus. But you can lower your risk for certain conditions that cause a larger uterus.
How to lower your fibroid risk
Here are some ways to lower your risk for fibroids.
Eat more fruits and vegetables. A diet rich in fruits and veggies may lower your chances for fibroids.
Try to eat foods high in fiber to clear out excess estrogen, such as:
- Apples
- Citrus fruits
- Tomatoes
- Broccoli
- Cauliflower
- Cabbage
Try low-fat dairy. Some studies suggest calcium-rich, low-fat dairy products may lower your fibroid risk. Extra points for yogurt with probiotics — it can support your gut health, too.
Boost your vitamin D. Low vitamin D levels may be linked to a higher fibroid risk.
You can get vitamin D from:
- Fatty fish, such as salmon and tuna
- Fortified dairy or cereals
- Egg yolk
- Beef liver
- Plant-based milk
- Supplements (check with your doctor first)
Stay active to reach your target weight. Exercise regularly. A healthy lifestyle can support your hormone balance. Set small, reachable goals to get to your target weight. Try short walks with a friend or family member.
Lower your blood pressure. Keep your blood pressure under control, and avoid alcohol to lower your risk for fibroids.
Practice lowering your stress. Stress can upset the balance of your hormones. And higher estrogen levels raise your risk for fibroids, adenomyosis, and certain uterine cancers. Try yoga, meditation, or deep breathing.
When to See a Doctor
If you have any unusual bleeding, get checked. Your OB/GYN can help you figure out what's causing the spotting. Some symptoms may need medical treatment.
Call and see your OB/GYN if you have:
- Heavy or long periods (can cause anemia)
- Bleeding between periods
- Serious pain or pressure in your pelvic area that does not go away
- Pain during sex
- A feeling of fullness or heaviness in your belly
- Sudden change in your menstrual cycle pattern
- Trouble peeing (or if you feel pressure on your bladder)
- A difficult time getting pregnant or pregnancy loss
- Sudden change in your belly size or if you can feel a lump in your belly
Takeaways
An enlarged uterus is a condition in which the uterus, which is a muscular organ, gets larger than normal. Pregnancy can make your uterus larger, but fibroids, adenomyosis, and uterine cancer can also cause it. If you have any unusual spotting or belly size changes, talk to your doctor to figure out if it's due to an enlarged uterus and the cause of your enlarged uterus.
Enlarged Uterus FAQs
Can an enlarged uterus affect fertility?
Some medical conditions that enlarge your uterus may affect fertility. Fibroids can make it harder for an embryo to implant — especially if they grow into the middle of your uterus. Talk to your OB/GYN or fertility specialist about treatment options and future pregnancy.
Is an enlarged uterus a sign of cancer?
It's not as common, but an enlarged uterus can be a sign of uterine cancer. But more often, an enlarged uterus is caused by fibroids or adenomyosis.
Can an enlarged uterus be treated without surgery?
Yes, you may not need surgery if fibroids or adenomyosis cause your enlarged uterus. Nonsurgical treatments can include:
- Pain relievers, iron supplements, or hormone therapies
- Focused ultrasound surgery (FUS), which destroys fibroids with sound waves
- Uterine artery embolization (UAE), which uses particles to shrink fibroids or adenomyosis
- Endometrial ablation, which destroys the uterine lining (to reduce heavy bleeding caused by fibroids or adenomyosis) with heat, cold, or radio waves
Can an enlarged uterus go back to normal size?
Your uterus usually goes back to normal size after perimenopause or pregnancy. But you may need treatment for an enlarged uterus caused by a fibroid, adenomyosis, or uterine cancer.
Does an enlarged uterus cause a big belly?
Your belly can get big if your uterus is enlarged. Sometimes, the larger lumps caused by fibroids or adenomyosis can make your belly look bigger — even pregnant-sized.
