Updated: Sep 25
The differences between a fibroid, cyst, & polyp is a common question as they all have similarities. In short, endometrial polyps, ovarian cysts, and uterine fibroids are different growths in or on the uterus or ovaries. They are abnormal, but they are not always cancerous. Fibroid Specialist Dr. Michael Lalezarian explains the differences between fibroids, cysts, and polyps, and what you can do if you suspect that you have one of them.
In this Article
Differences between uterine fibroids, ovarian cysts, and endometrial polyps
Uterine fibroids overview
Ovarian cyst overview
Endometrial polyp overview
What to do if you suspect a fibroid, cyst, or polyp
Differences Between Uterine Fibroids vs Ovarian Cysts vs Endometrial Polyps
Uterine fibroids are firm, muscular growths located within the uterine wall or on the surface of the uterus that are usually non-cancerous.
Appearance: Firm, mostly white in color with surface blood vessels
Size: Less than 1 inch up to several inches in diameter
Symptoms: Abnormal uterine bleeding, pelvic pain, or pressure
Cancer Risk: Less than 1 in 1,000 cases
Reproductive Effects: Large fibroids > 5 to 6 cm and those that distort the uterine cavity may increase the risk of pregnancy complications and contribute to infertility
Endometrial polyps are soft overgrowths that project from the surface of the endometrium, the mucous membrane lining the uterus. Most endometrial polyps are benign, but some can be cancerous.
Appearance: Beefy red, thinner, and more mobile than a fibroid; soft and readily tears or bleeds when gently touched or manipulated with instruments
Size: Few millimeters to several centimeters
Symptoms: Abnormal uterine bleeding
Cancer Risk: About 5 in 100 cases
Reproductive Effects: Limited information, but several studies show no significant negative impacts on fertility or pregnancy
Ovarian cysts are fluid-filled sacs that can develop in or on either ovary, usually forming during ovulation. Most ovarian cysts are benign.
Appearance: Fluid-filled sac
Size: Less than half an inch up to 4 inches or greater in diameter
Symptoms: Sharp, lower abdominal pain
Cancer Risk: Less than 1 in 100 cases
Reproductive Effects: Usually none, but rupture or torsion caused by a cyst can damage an ovary and affect fertility; polycystic ovary syndrome is often associated with infertility
Pelvic pain or pressure and abnormal uterine bleeding are common symptoms of uterine fibroids, ovarian cysts, and endometrial polyps. Sometimes, these growths can contribute to infertility or increase pregnancy complications. The optimal treatment for fibroids vs cysts vs polyps is determined by patient fertility goals, symptom severity, and preference for conservative therapy or invasive surgical intervention.
Should I be Worried About Endometrial Polyps?
Endometrial Polyps are soft overgrowths that project from the surface of the endometrium, the mucous membrane lining the uterus. Most endometrial polyps, also known as uterine polyps, are benign. However, some can be cancerous. According to one study, approximately 95 percent of endometrial polyps are benign . In general, endometrial polyps are more commonly found in older, postmenopausal women. This is because women of reproductive age regularly shed the endometrium during menstruation, while menopausal women do not. In one systematic review including over 10,000 women, the incidence of malignant and pre-cancerous polyps was significantly higher in postmenopausal compared to premenopausal women .
There is limited information regarding the effects of endometrial polyps on fertility. In the few studies that have been published, it was found that endometrial polyps do not significantly increase the risk of adverse obstetric outcomes . In one study, the prevalence of uterine polyps was the same in women with a recent miscarriage as it was with the general population .
Symptoms of Endometrial Polyps
Not all uterine polyps will cause symptoms. However, the most common symptom of endometrial polyps is abnormal uterine bleeding. This includes:
Heavy bleeding between menstrual periods (intermenstrual bleeding)
Vaginal bleeding after physical activity or sexual intercourse
Heavy bleeding during menstruation
The presence of an endometrial polyp is confirmed with pelvic ultrasound imaging or hysteroscopy, a procedure that involves inserting a thin, lighted tube with a camera into the vagina to examine the inside of the uterus. If the polyp is concerning for possible cancer, your OB-GYN will perform an endometrial biopsy to check for cancer or precancerous cells.
Endometrial Polyp Removal
Symptomatic endometrial polyps are more likely to be malignant and precancerous. Therefore, they should be removed in premenopausal and postmenopausal women. This is usually done through a polypectomy procedure under hysteroscopic guidance, where small surgical instruments are inserted through a thin and lighted tube to remove the polyp .
Women with asymptomatic uterine polyps may benefit from polyp removal if they have additional risk factors that increase their chances of developing endometrial cancer. However, most asymptomatic endometrial polyps are managed with watchful waiting to see if they will resolve on their own over time.
Should I be Worried About Uterine Fibroids?
Uterine fibroids, also known as leiomyomas or myomas, are typically noncancerous growths on or within the uterus. Most fibroids are not thought to be cancerous, but sometimes fibroids can be confused with a mass in the uterus that may actually be a rare, cancerous tumor . Uterine fibroids are discovered incidentally on imaging or when they cause symptoms. They are very common, with an estimated lifetime risk of 70-80% depending on race and other factors . Most myomas are small and asymptomatic.
Some uterine fibroids can impact fertility, such as those that distort the uterine cavity. Meanwhile, serosal fibroids located away from the uterine cavity and endometrial lining are less likely to negatively impact fertility. Because the likelihood of uterine fibroids and miscarriage both increase with increasing age, it is difficult to say if uterine fibroids alone are the main driving factor for reproductive dysfunction .
Symptoms of Uterine Fibroids
Fibroids can be symptomatic or asymptomatic. Patients can have one or more of the following common symptoms of uterine fibroids:
Heavy or prolonged menstrual bleeding
Bulk symptoms such as pelvic pain, pressure, or bloating
Pelvic pain or very painful menstruation
Infertility or recurrent miscarriages
Low back pain and abdominal and urinary symptoms are also associated with uterine fibroids.
Pelvic ultrasound imaging is usually the first-line study used to confirm the location, number, and size of uterine fibroids. With hysteroscopy, a thin tube and camera can be inserted through the vagina to further visualize the uterus and characterize any fibroids.
Treatment of Uterine Fibroids
There are many treatments available for uterine fibroids, however not all treatments will preserve a patient’s fertility. Symptom severity and type will help determine the appropriate treatment, as will patient fertility goals.
For women who do not wish to become pregnant in the future, medical therapy with pain medication and birth control can help to relieve symptoms. However, they will not eliminate the fibroids. Most leiomyomas shrink after menopause, but this is not true for all women .
Should I be Worried About an Ovarian Cyst?
Ovarian cysts are fluid-filled sacs that can develop in or on either ovary. They are commonly found in pre-menopausal women and are usually benign. Cancer is the cause of ovarian cysts in less than 1 in 100 cases .
In most cases, an ovarian cyst forms when a follicle on an ovary responsible for releasing an egg fails to open during ovulation. This being the case, many reproductive-aged, pre-menopausal women can develop an ovarian cyst. On the other hand, ovarian cysts are a lot less common in post menopausal women [9,10].
Ovarian cysts can be a natural part of ovulation, and most cysts resolve on their own in a few months without any intervention [9,10]. However, ovarian cysts can be worrisome if they demonstrate the potential to rupture or cause the ovary to twist on itself (ovarian torsion). If the ovarian cyst is abnormally large, appears complex with solid areas or nodules on the surface, and you have a family history of ovarian or other types of cancer, this may also increase the concern for possible malignancy [9,10].
In polycystic ovary syndrome (PCOS), many small cysts form on the ovaries. Infertility is common in patients with PCOS.
Pelvic ultrasound is a sensitive method for detecting ovarian cysts.
Symptoms of an Ovarian Cyst
Often, ovarian cysts will cause no symptoms at all. However, if symptomatic, ovarian cysts may produce:
Lower abdominal pain or pelvic pressure
Sudden and severe sharp pain immediately after sexual intercourse mid-menstrual cycle
Sudden and severe sharp pain if an ovarian cyst bursts
Nausea or vomiting along with pain if the cyst causes ovarian torsion
Does an Ovarian Cyst Need to be Removed?
Ovarian cysts in premenopausal women usually resolve on their own without treatment, and few cause complications as severe as ovarian torsion, significant rupture, or cancer. Your OB-GYN may recommend watchful waiting with periodic pelvic ultrasounds.
Alternatively, your doctor might prescribe birth control pills to stop cysts from growing and to prevent new cysts from developing during ovulation.
If your ovarian cyst continues to cause persistent pelvic pain, is suspicious for cancer, or is at risk of rupturing or causing ovarian torsion, your health care provider may recommend surgery to remove the cyst. Surgical removal of an ovarian cyst is called a cystectomy. During this procedure, the ovaries are kept intact [9,10].
What to Do if You Suspect a Polyp, Fibroid, or Cyst
If you suspect that you have a polyp, fibroid, or cyst, you should schedule an appointment with your OB-GYN or a specialist to discuss your symptoms. A pelvic examination and a pelvic ultrasound is usually sufficient to tell whether or not you have an abnormal growth. Additional imaging or tests may be conducted to determine if it’s a polyp, fibroid, or cyst. Your doctor might also recommend biopsying your tissue if it is concerning for cancer.
About the Author
Dr. Michael Lalezarian is a practicing interventional radiologist with the Fibroid Specialists of University Vascular in Los Angeles, CA. In addition to patient care, Dr. Lalezarian teaches and supervises medical students, residents, and fellows as a full time teaching Professor in the Department of Radiology at UCLA. He is regarded as an expert in uterine fibroid embolization. You can view Dr. Lalezarian's full bio here.
This blog post was written with research and editorial assistance from OnChart™.
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