What are Uterine Polyps?

Uterine polyps are small, benign protrusions of tissue that grow on the uterine lining (endometrium). They are overgrowths of the same kind of cells as the lining itself and may appear as finger-like projections or little mushrooms. As they grow, they become fragile and bleed, and as such, they are a common cause of abnormal uterine bleeding.

Occasionally a polyp may grow on or through the cervix and cause irritation and irregular bleeding. This type of polyp can be seen during a pelvic examination when the doctor examines the cervix through a speculum.

Are polyps a sign of precancer?

In other tissues, such as the colon, polyps have long been considered an “early warning sign” of cancer; in contrast, uterine polyps are thought to be generally benign. However, with the increased use of pelvic sonograms, more polyps are now being detected, and a recent study found that the rate of polyps with abnormal cells was nearly 16% among women who opted to have them removed. In 2% of the women, endometrial cancer was found. The authors of the study recommend that women with polyps should be encouraged to have them removed, given the high rate of abnormal pathology and the relative ease of treatment.

Symptoms

It’s possible to have uterine polyps without signs or symptoms. However, some signs of uterine polyps include:

Irregular menstrual bleeding - for example, having frequent, unpredictable periods of variable length and heaviness
Bleeding between menstrual periods
Excessively heavy menstrual periods
Vaginal bleeding after menopause
Infertility

Prevalence

You’re at greater risk of developing uterine polyps if you:

Are age 40 to 50
Are pre- or peri-menopausal
Are obese
Take tamoxifen, a drug therapy for breast cancer
Have high blood pressure (hypertension)
Have cervical polyps

Cause

Although the exact cause of uterine polyps is unknown, hormonal factors appear to play a role. Uterine polyps are estrogen-sensitive, meaning that they respond to estrogen in the same way that the lining of your uterus (endometrium) does - growing in response to circulating estrogen.

There is no specific method for preventing uterine polyps, although keeping yourself at a healthy weight, with normal blood pressure readings are the best methods of lessening your risk factors.

How do I know that I have polyps?

If your doctor suspects that you have uterine polyps, he or she might perform one of the following tests or procedures:

Transvaginal ultrasound. A slender, wand-like device placed in your vagina sends out sound waves and creates an image of your uterus, including its interior. A related procedure, known as hysterosonography, involves having salt water (saline) injected into your uterus through a small tube (catheter) threaded through your vagina and cervix. The saline expands your uterine cavity, which gives the doctor a clearer view of the inside of your uterus.
Hysteroscopy. Doctors may perform a procedure called hysteroscopy to diagnose and treat uterine polyps. In a hysteroscopy, your doctor inserts a thin, flexible, lighted telescope (hysteroscope) through your vagina and cervix into your uterus. Hysteroscopy allows your doctor to examine the inside of your uterus and remove any polyps that are found. This eliminates the need for a follow-up procedure.
Curettage. Your doctor uses a long metal instrument with a loop on the end (curret) to scrape the walls of your uterus. This may be done to collect a specimen for laboratory testing (biopsy) or to remove a polyp. Curettage may be performed on its own (blind curettage) or with the guidance of a hysteroscope.

Polyp Treatment Options

Possible treatments for uterine polyps include:

Watchful waiting. Small, asymptomatic polyps may resolve on their own. Treatment is unnecessary unless you’re at risk of uterine (endometrial) cancer.
Medication. Certain hormonal medications, including progestins and gonadotropin-releasing hormone agonists, may shrink a uterine polyp and lessen symptoms. But taking such medications is usually a short-term solution at best - symptoms typically recur once you stop taking the medicine.
Surgical removal (excision). If you undergo hysteroscopy, instruments inserted through the hysteroscope - the device your doctor uses to see inside your uterus - make it possible to cut away and remove polyps once they're identified. The removed polyp may be sent to a laboratory for microscopic examination.
Hysterectomy. If closer examination reveals that a uterine polyp contains cancerous cells, surgery to remove your uterus (hysterectomy) becomes necessary.

Polyp Facts

Uterine polyps, once removed, can recur. It's possible that you might need to undergo treatment more than once if you experience recurring uterine polyps.
Some say that uterine polyps can lead to infertility. This issue still requires further tests but if a woman has uterine polyps and she’s experiencing infertility, the removal of the polyps may improve her fertility.
The presence of uterine polyps also increases the risks of miscarriage for pregnant women. Women who enter into in vitro fertilization treatment, are generally advised to have uterine polyps removed before conducting any embryo transfer procedure.

References

American Society for Reproductive Medicine. Pelvic Pain: A Guide for Patients. Patient Information Series 1997. www.asrm.org/patients/patientbooklets/pelvicpain.pdf.
Dolloff A, et al. Endometrial polyps and risk of hyperplasia and neoplasia. J Minimally Invasive Gynecol. 2006;13(5):S75-76.
Parker WH. A Gynecologist’s Second Opinion. (c)2003; A Plume Book; Published by the Penguin Group, New York, NY.
Munro M. Abnormal uterine bleeding in the productive years. Part I: Pathogenesis and clinical investigation. J Am Assoc Gynecologic Laparoscopists. 1999;6:393-416.