Crash course on uterine fibroids

Uterine fibroids are highly common - and highly bothersome. Read on to learn what causes fibroids and how they can be prevented.

If you have gone to the OBGYN with complaints of bad cramping or heavy periods, it’s possible that you were checked for having a benign tumor in your uterus called a “fibroid.” But, while some people feel clear symptoms with fibroids, others experience no signs whatsoever and the growths can come and go without a notice.

In this article we will be providing an overview of all things uterine fibroids, including answers to the following questions:

  • What are uterine fibroids?
  • What are symptoms of fibroids?
  • What are the different types of fibroids?
  • What causes fibroids?
  • How are fibroids diagnosed?
  • Can fibroids be cured? What are common treatment strategies?

What are uterine fibroids?

Uterine fibroids are tumors consisting of smooth muscle cells and fibrous connective tissue.

As the most common type of tumor in the reproductive tract, they are routinely found in 70 to 80% of women, often during pelvic exams.

All fibroids grow at different rates, and can range from the size of a pea to a  watermelon, although the latter is much more infrequent.

Uterine fibroids are usually noncancerous (benign) —it is rare to have cancerous fibroids. If a fibroid starts as noncancerous it cannot become cancerous later on.

Lastly, in terms of who fibroids affect, they generally can develop in females that are between the ages of 18 - 40, most commonly occurring in those aged 30 - 40 years.

What are symptoms of fibroids?

Below are all of the symptoms commonly seen with uterine fibroids—although none of these symptoms are necessary to have fibroids. Many women will not develop any symptoms at all.

  • Heavy periods
  • Prolonged periods
  • Bleeding between periods
  • Sudden weight gain or bloating
  • Pelvic Pain or Pressure
  • Backaches or leg pain
  • Pain during intercourse
  • Frequent urination
  • Lower back pain
  • Infertility

What are the different types of fibroids?

Not all fibroids are the same. There are a variety of types of these uterine tumors, all with unique characteristics.

As symptoms and treatment may vary depending on the type of fibroid (or fibroids) one is experiencing, it’s important to have a basic understanding of how they differ.

Subserosal fibroids

  • These fibroids are the most common fibroids and grow outside of the uterus into the pelvis.
  • Because they are not limited to the space within the uterus, these fibroids tend to grow larger and often have delayed on-set of symptoms.
  • They can have a stalk connecting the fibroid to the uterus—these stalks are called pedunculated fibroids.

Intramural fibroids

  • These fibroids grow in the muscular wall of the uterus.
  • If left untreated, these fibroids can grow very large.
  • It is common to have multiple intramural fibroids in the same area.

Submucosal fibroids

  • These uncommon fibroids can grow into the open space inside the uterus or within the uterine wall.
  • Since submucosal fibroids directly interact with the uterine lining, the fibroids commonly cause heavy bleeding during and between periods.
  • Like the Subserosal fibroids, they can also have a stalk connecting the fibroid to the uterine wall.

What causes fibroids?

A direct cause of uterine fibroid growth is somewhat unknown, but assumed to have a genetic and lifestyle component.

Genetic predispositions include family history and ethnic origin — as mentioned, Black females are 3x more likely to develop fibroids than white females and also at an increased risk of developing more severe symptoms.

Moreover, individuals who are obese or overweight are at a 2 - 3x higher risk of developing fibroids than those whose weight falls within “normal” ranges.

Hormonal fluctuations are another risk factor that can increase one’s chance of developing fibroids.

  • Menopause and perimenopause are times when fibroid risk increases, due to the hormonal fluctuations that occur during this season of life. After menopause, fibroids become less likely to form and can shrink.
  • Changes that occur due to Hormonal Replacement Therapy (HRT), or supplemental hormones, also can lead to fibroids. This is due to their ability to disrupt an equilibrium of hormonal interactions in your body.

Hormonal changes like these can lead to fibroids for a variety of reasons. One catalyst is that estrogen and progesterone —the two hormones associated with the growth of the uterine lining each month— appear to also stimulate fibroid development.

After repeatedly dividing after years of menstrual cycles, uterine fibroid stem cells are believed to change in texture to become firm and rubbery.

Fibroid cells contain more estrogen and progesterone receptors than normal uterine muscle cells, indicating they respond to hormonal secretion and may be more likely to develop in individuals with higher levels of estrogen and progesterone.

In menopause, when hormonal production decreases significantly, uterine fibroids stop growing and often shrink in size.

How are fibroids diagnosed?

Fibroids may be initially found through a physical exam by a healthcare provider. They can be felt as a firm irregular lump around the abdomen or pelvis.

Two types of scans can confirm the presence of fibroids:

  • Ultrasound: Ultrasounds are the most common scan for fibroids. This is an imaging procedure that sends sound waves over uterus and ovaries. Ultrasounds are generally accurate, quick, and simple, depending on the skill of the technician or doctor.
  • Magnetic Resonance Imaging (MRI): An MRI uses magnets and radio waves for imaging can provide a more precise picture of what is happening with your fibroids, and is helpful for determining size, number, and more accurate location. An MRI is also helpful for differentiating between fibroids and adenomyosis and determining what treatment is necessary.

What are other procedures to be aware of with uterine fibroids?

To monitor fibroids and check for complications, your OBGYN will likely conduct various other procedures.

For infertility issues, a hysterosalpingogram (HSG) checks the inside of the uterus and the fallopian tubes to look for blockages or scarring.

To confirm presence of uterine polyps or fibroids in patients with heavy bleeding, a hysterosonogram is an X-ray scan inside the uterus with water injections.

Your provider also may want to perform a laparoscopy to rule out endometriosis. This procedure uses a laparoscope (a long, thin instrument with a light and camera) to look at the uterus and surrounding structures via a small incision above or in the navel.

If you or your provider wants to look for fibroids or endometrial polyps in the uterus without making an incision, a hysteroscopy looks at the uterus with a laparoscopic camera through vagina and cervix.

How are fibroids different from polyps?

Fibroids and polyps can present with similar symptoms; heavy bleeding or prolonged periods, and potentially bleeding between periods. But there are several key differences to be aware of.

Fibroids present with more pain, cramping, fatigue and bloating, while polyps often present with more severe and irregular bleeding than fibroids.

Moreover, fibroids are made up of connective fibrous tissue while polyps are made of endometrial tissue.

Lastly, uterine fibroids rarely are cancerous and cannot develop into cancerous fibroids once benign. In contrast, polyps can (and more often do) become cancerous as they grow.

Treatment for uterine fibroids

While there is no known “cure” known to prevent fibroids from returning, surgery can remove existing fibroids and diet and lifestyle changes has been shown to lower risk of new fibroids developing.

Lifestyle Changes:

  • Complementary Lifestyle Changes to lessen symptoms (or even relieve them). This includes dietary changes, vitamins & supplements, exercise, and mindfulness therapies such as yoga and meditation.

Medical Treatments

Some fibroids may need a more active treatment, depending on one’s symptoms, age, fertility goals, other health conditions, previous fibroid treatments, or the number and size of fibroids.

  1. Hormonal therapy is a non-invasive way to regulate the menstrual cycle and treat symptoms such as heavy menstrual bleeding and pelvic pain or pressure.
  • There are different types of hormonal therapy; including but not limited to progestin-releasing intrauterine devices (IUDs), or gonadotropin-releasing hormone (Gn-RH) agonists.
  1. Non-hormonal therapies can be a helpful way to manage symptoms or treat fibroids without generating hormonal changes.
  • NSAIDs — for periodic pain management
  • Tranexamic acid (TXA) —a medication that is used to help boost the body’s ability to form blood clots.
  • TXA can decrease vaginal bleeding although this is generally not used as a long-term solution and only for severe circumstances.
  • MRI-guided HIFU —This treatment is a non-invasive procedure in which an MRI is paired with high intensity focused ultrasound (HIFU).
  • The MRI locates the fibroids and the HIFU sound waves create thermally ablate (burn away) the fibroid.
  • MR-guided HIFU is only used for small or medium-sized fibroids.
  • Individuals often choose this treatment when they are trying to preserve their fertility.
  • Uterine artery embolization — A radiologist will block the artery supplying a fibroid with blood, essentially cutting off its energy supply.
  • Watchful Waiting
  • Most fibroids are left alone — with no interventions. They tend to stop growing and shrink as an individual approaches menopause.
  • Doctors often initially recommend observation (AKA “watchful waiting”) to make sure they don’t grow or multiply to a concerning degree.

Other (rare) complications of uterine fibroids:

Although much less common, uterine fibroids can lead to kidney damage, anemia from heavy bleeding, or infertility or miscarriage.


Jocelyn Spizman

Jocelyn is a certified crisis counselor and health journalist passionate about integrative healthcare, plant-based nutrition, and socio-cultural determinants of health. She double majored in Human Health at Emory University and aspires to make biomedicine more digestible and explore cultural wellness phenomena.