Endometrial Polyp: Symptoms, Causes, and Treatment

An endometrial polyp is a small growth in the lining of the uterus (the endometrium). If you’re a woman experiencing unexplained irregular bleeding or spotting, an endometrial polyp could be a cause. The most common symptom of an endometrial polyp is abnormal vaginal bleeding – for example, heavy periods or bleeding between cycles[37]. Many endometrial polyps are benign (non-cancerous), but they can be annoying and sometimes impact fertility or pregnancy. This friendly guide will walk you through what endometrial polyps are, the symptoms to watch for, why they happen, and how doctors treat them. Our goal is to give you clear, medically accurate information so you feel empowered about your reproductive health.

What Is an Endometrial Polyp?

An endometrial polyp is a growth on the inner wall of the uterus. It forms when the uterine lining (endometrium) overgrows in a specific spot. Polyps can be round or oval in shape and range in size from as small as a sesame seed to as large as a golf ball in rare cases[38]. They are attached to the uterine wall either by a thin stalk or a broad base, extending inward into the uterine cavity[39][40]. You can have just one polyp or several at once.

Another term for an endometrial polyp is a uterine polyp – they mean the same thing[40]. These growths are usually benign, meaning they are not cancerous. About 95% of endometrial polyps are noncancerous, and only a small percentage (around 5% or less) have precancerous or cancerous cells[41]. The risk of cancer is slightly higher if you are postmenopausal or if the polyp causes bleeding.

Endometrial polyps can occur in women of any age, but they are most common in your 40s and 50s, around the time of perimenopause[42]. They can also occur after menopause and occasionally in younger women, though it’s uncommon under age 20[43]. Hormones likely play a role – these polyps seem to be influenced by estrogen (the hormone that causes the endometrial lining to thicken each month).

Key characteristics of endometrial polyps: – Usually benign growths in the uterus lining. – Sizes vary; most are small, but some can grow a few centimeters. – Often attached by a stalk (think of a skin tag, but inside the uterus) or a flat base on the uterine wall. – Can be solitary or multiple. – Sometimes they protrude through the cervix into the vagina (if on a long stalk), but usually they remain inside the uterus.

Many endometrial polyps do not cause symptoms. It’s possible to have a polyp and not know it, only discovering it during a routine exam or an ultrasound done for another reason[44]. However, when symptoms do occur, abnormal bleeding is the hallmark.

Symptoms of Endometrial Polyps

The majority of symptomatic endometrial polyps present with some form of abnormal uterine bleeding[37]. Here are the common symptoms associated with these polyps:

• Irregular menstrual periods: Your periods may come unpredictably or with irregular spacing. For example, you might skip a month and then have a very heavy period, or have bleeding two weeks apart. Polyps can disrupt the normal menstrual cycle timing[45].
• Heavy menstrual bleeding: Some women experience unusually heavy flow during their periods due to endometrial polyps[46]. If you’re soaking through pads or tampons faster than every 1-2 hours, or your period lasts longer than a week, a polyp could be contributing to that heavy bleeding.
• Spotting or bleeding between periods: Any bleeding that occurs when you’re not on your period (known as intermenstrual bleeding) is a red flag for a polyp[47]. You might notice light spotting or a full “extra” period out of sync with your cycle.
• Bleeding after intercourse: Some women with endometrial polyps have post-coital bleeding, meaning a small amount of blood after sex[48]. The polyp can be sensitive and bleed when touched or if the cervix is bumped during intercourse.
• Bleeding after menopause: If you have gone through menopause (no periods for a year or more) and experience any vaginal bleeding or spotting, it could be due to a uterine polyp[45][49]. Postmenopausal bleeding is always something to have evaluated by a doctor, and polyps are a common benign cause.
• Infertility or difficulty getting pregnant: Endometrial polyps can sometimes interfere with fertility. Some women with polyps have trouble conceiving or have had recurrent miscarriages. A polyp may act like an “occupier” in the uterus, making it harder for an embryo to implant, or it could cause inflammation that hinders pregnancy. In fact, infertility can be a sign of an undetected polyp[47]. The good news is that removing the polyp often improves fertility outcomes in these cases.
• Pelvic cramping or pain: Most polyps are not painful. However, a very large polyp might cause dull pelvic pain or cramping in the lower abdomen, somewhat similar to menstrual cramps[50]. This is relatively uncommon. Also, if a polyp protrudes through the cervix, it could cause discomfort. Generally, pain is not a typical symptom of endometrial polyps.

It’s worth emphasizing that many women with endometrial polyps have no symptoms at all. Some polyps are discovered during evaluations for other issues (like an ultrasound for fibroids or fertility testing). However, if you do experience the above symptoms – especially abnormal bleeding – it’s important to see a healthcare provider. Abnormal uterine bleeding has several possible causes, and a thorough check-up can determine if a polyp is present.

Important: Anytime you have bleeding after menopause, or very heavy periods, or bleeding between periods, you should consult a doctor. These symptoms aren’t normal and merit investigation. Endometrial polyps are a common benign explanation, but your provider will want to rule out other causes as well.

Causes and Risk Factors

The exact cause of endometrial polyps isn’t fully understood. Doctors know it’s related to an overgrowth of the endometrial tissue, but why that focal overgrowth occurs in some women and not others is still being studied[51]. Here’s what is known:

• Hormonal influence: Endometrial polyps are estrogen-sensitive Estrogen is the hormone that makes the uterine lining thicken each cycle in preparation for possible pregnancy. If estrogen levels are high or if the lining responds too strongly to estrogen, it can form polyps. Many risk factors for polyps involve exposure to higher estrogen (either your own estrogen or from medications)[51]. For instance, during perimenopause, estrogen can fluctuate and sometimes dominate over progesterone, which might trigger polyp formation.
• Age and life stage: Being in your 40s or 50s (perimenopausal age) is a major risk factor for developing uterine polyps[42]. This is likely because of the hormonal changes in midlife. Polyps can also occur after menopause, especially if a woman is on hormone replacement therapy. It’s relatively rare to see endometrial polyps in young women under 30, and extremely rare under 20.
• Obesity: Women who are overweight or obese have a higher risk of developing endometrial polyps[52]. Excess fat tissue increases estrogen levels in the body, which could contribute to polyp growth.
• High blood pressure: Some studies have noted an association between hypertension (high blood pressure) and uterine polyps[52]. The reason isn’t entirely clear, but it might reflect underlying metabolic issues that also tie into estrogen levels.
• Tamoxifen use: Tamoxifen is a drug used to treat breast cancer by blocking estrogen receptors in breast tissue. Paradoxically, tamoxifen has a mild estrogen-like effect on the uterus. Women taking tamoxifen have an increased risk of developing endometrial polyps[53]. If you’re on tamoxifen, your doctor will usually monitor your uterus periodically for this reason.
• Hormone Replacement Therapy (HRT): Postmenopausal women on HRT that includes estrogen (especially without sufficient progesterone) may have a higher chance of polyps forming[54]. High-dose estrogen stimulation of the endometrium, if not balanced, can lead to polyps.
• Genetic factors: Though rare, certain hereditary conditions can raise the risk. For example, Lynch syndrome and Cowden syndrome are genetic disorders that can increase the likelihood of uterine growths, including polyps[55]. These syndromes are uncommon, but if they run in a family, doctors may be more vigilant in screening for polyps.

In summary, endometrial polyps tend to thrive in an estrogen-rich environment. Women who have higher levels of estrogen or greater endometrial stimulation (due to the factors above) are more prone to get them. Researchers are still exploring why some women get multiple polyps and others get none; it could be a mix of genetic predisposition and environmental factors.

It’s also notable that having had a polyp before slightly raises your risk of another. There’s some evidence that people who have had polyps in the past are somewhat more likely to develop new ones in the future compared to those who never had any[56]. This could be because whatever conditions allowed the first polyp to form might still be present (e.g., hormonal environment). Regular follow-ups with your doctor after a polyp diagnosis are wise, especially if symptoms reappear.

How Are Endometrial Polyps Diagnosed?

If your doctor suspects an endometrial polyp (often based on symptoms like irregular bleeding), several tests can confirm the diagnosis:

• Transvaginal Ultrasound: This is usually the first step. A transvaginal ultrasound involves inserting a small ultrasound probe into the vagina to get a clear image of the uterus. Polyps might appear as round or elongated growths inside the uterine cavity on the ultrasound. Sometimes, a regular ultrasound shows a thickened lining, prompting further investigation[57]. It’s a quick and painless procedure done in the office.
• Sonohysterography (saline-infusion ultrasound): If a standard ultrasound is unclear, the doctor may do a specialized ultrasound. In this procedure, a small amount of sterile saline (salt water) is injected into the uterus via a thin catheter during ultrasound[58]. The saline expands the cavity slightly, which helps outline any polyps or irregularities more clearly. This can provide a better view of small polyps.
• Hysteroscopy: This is a minor procedure where the doctor inserts a thin, lighted telescope (hysteroscope) through the cervix to directly visualize the inside of the uterus[59][60]. Hysteroscopy allows the doctor to see polyps if they are present, and it can be combined with removal at the same time (more on treatment below). It’s often done under light anesthesia or sedation. Hysteroscopy is very useful because it gives a definitive look inside the uterine cavity.
• Endometrial Biopsy: In some cases, especially if there is concern about the nature of the tissue, a doctor might take a small sample of the uterine lining (biopsy) for analysis[61]. This can sometimes catch a polyp or at least tell if the lining is overgrown. However, a blind biopsy might miss a polyp if it doesn’t sample that exact area. Biopsy is more often used to rule out other issues (like endometrial hyperplasia or cancer) in women with abnormal bleeding.
• Dilation and Curettage (D&C): This is a procedure where the cervix is dilated and a special instrument is used to scrape the uterine lining[61]. A D&C can be used to remove polyps or sample tissue. However, it’s not as targeted as hysteroscopic removal, so it’s less commonly used solely for polyps unless combined with hysteroscopy. In the past, D&C was a common way to address abnormal bleeding (and could incidentally remove polyps), but nowadays, hysteroscopy gives a more precise approach.

Usually, the process might be: ultrasound first, and if a polyp is seen or strongly suspected, then a hysteroscopic exam to confirm and possibly treat it. If you are being evaluated for infertility, doctors might find a polyp during a routine uterine cavity exam (like a hysterosalpingogram or during IVF evaluations) even if you had no bleeding symptoms.

Treatment of Endometrial Polyps

When it comes to treating an endometrial polyp, the mainstay is removal of the polyp, especially if it’s causing symptoms or is sizable. Here’s what you need to know about treatment:

• Watchful Waiting: If a polyp is very small and not causing any symptoms, and if you are premenopausal, your doctor might take a conservative approach. Sometimes, small polyps can resolve on their own or remain stable[62][63]. In a premenopausal woman with no symptoms, a low-risk polyp might just be monitored over time. You would follow up periodically (for example, repeat an ultrasound in a few months) to see if it’s gone or changed. However, for women who are postmenopausal or who have bothersome symptoms, treatment is generally recommended rather than observation[63].
• Medication (temporary): There are some medications that can help manage symptoms of polyps, but they are usually a short-term fix. Hormonal medications like progestins or GnRH agonists can sometimes shrink polyps or at least lessen the bleeding[64]. For instance, a doctor might prescribe a progestin (which opposes estrogen’s effect on the lining) to see if bleeding improves. However, the relief is often temporary – once medication is stopped, symptoms tend to return[64]. Medication is not a definitive cure for polyps, but it might be used in specific cases (like to stabilize bleeding before surgery, or if someone cannot undergo surgery immediately).
• Uterine Polypectomy (Hysteroscopic Removal): This is the most common and effective treatment. A polypectomy means the polyp is removed. Typically, this is done via hysteroscopy: the doctor inserts a hysteroscope through the cervix, visualizes the polyp, and then uses tiny instruments to cut and remove it[65]. Because the doctor can see exactly what they’re doing, hysteroscopic removal is very precise – the whole polyp (stalk and all) can be excised. The procedure is often outpatient (meaning no overnight hospital stay). Recovery is quick, with maybe a day or two of mild cramping or spotting afterwards. Removing the polyp should alleviate the associated symptoms (like abnormal bleeding) in most cases[66]. The removed tissue is always sent to a lab for analysis to confirm it’s benign[65].
• Post-removal: After a polyp is removed, your doctor will likely schedule a follow-up appointment. If the pathology report shows that the polyp had any precancerous or cancerous cells (which is uncommon, but possible), further treatment might be needed. This could range from close monitoring to more extensive surgery depending on the findings[67]. In the vast majority of cases, though, once the polyp is out and is confirmed benign, no additional treatment is necessary.
• Hysterectomy (rarely necessary): In cases where polyps keep recurring or if a polyp is found to contain cancer cells, a hysterectomy (surgical removal of the entire uterus) might be recommended[67]. This is generally a last-resort option for polyps, reserved for when malignancy is a concern or other uterine pathology exists. Most women will not need a hysterectomy for a simple endometrial polyp.

After treatment, the outlook is excellent. Studies show that removing polyps resolves symptoms in about 75–100% of cases[66], which means you’re very likely to get relief from issues like irregular bleeding once the polyp is gone. Polyps rarely grow back after removal[68]. If they do, it’s usually a new polyp rather than the same one, and it can be dealt with similarly. To ensure everything stays on track, your provider might recommend periodic check-ups, especially if you had multiple polyps or risk factors.

For women concerned about fertility, removing a polyp can sometimes improve the chances of conceiving (since the uterine environment is more favorable without that extra tissue). While research is ongoing, there is evidence that polyp removal can slightly boost fertility rates in those who had trouble conceiving with a polyp[68].

Prevention and Outlook

Unfortunately, there’s no guaranteed way to prevent endometrial polyps. They can occur even in women who are otherwise healthy and have normal hormone levels. However, being mindful of the risk factors (like maintaining a healthy weight and managing blood pressure) could theoretically help reduce risk. If you’re on tamoxifen or estrogen therapy, make sure to have regular follow-ups as advised by your doctor.

Regular gynecological check-ups are key in catching issues early[69]. Even though you can’t prevent polyps outright, early detection means simpler treatment and less chance for complications. If you experience any return of symptoms after a polyp removal, report it to your doctor – it could signal a recurrence that can be handled before it grows or causes problems.

The prognosis for benign endometrial polyps is excellent. They are one of the more straightforward gynecological conditions to treat. Once removed, most women have no further issues, and their symptoms (bleeding, etc.) resolve. Quality of life often greatly improves when you’re no longer dealing with unpredictable bleeding or anemia from heavy periods.

For that small subset of polyps that are precancerous or cancerous, the prognosis depends on ensuring appropriate treatment (which might involve additional surgery). However, because polyps often present with symptoms, they tend to be discovered, and any serious pathology can be addressed promptly.

In summary, if you’re diagnosed with an endometrial polyp, you can feel reassured that it’s a common and usually benign condition. You have options for treatment, and you’re not alone – many women experience this, especially in midlife. With proper care, an endometrial polyp can be managed effectively so you can get back to living your life without the nuisance of abnormal bleeding or other symptoms.

Key Takeaways

• Endometrial polyps (aka uterine polyps) are small growths in the lining of the uterus. They are typically benign, with about 95% being noncancerous[41].
• The most common symptom of an endometrial polyp is abnormal uterine bleeding[37]. This can include heavy or prolonged periods, spotting between periods, or bleeding after menopause. Some polyps also cause bleeding after sex or fertility issues.
• Many endometrial polyps are asymptomatic and might be found during exams for other reasons. However, if you have irregular menstrual bleeding or any bleeding after menopause, it’s important to get checked for polyps or other causes.
• Risk factors for developing polyps include being in midlife (40s-50s), having higher estrogen exposure (e.g., obesity, certain forms of hormone therapy, tamoxifen use), and possibly hypertension[52][54]. Polyp formation is linked to estrogen stimulating the uterine lining[51].
• Diagnosis is typically done via a transvaginal ultrasound, sometimes enhanced with saline (sonohysterogram) for clarity[57]. A hysteroscopy can directly visualize and confirm a polyp inside the uterus[59].
• The mainstay of treatment is removal of the polyp, usually with a minimally invasive hysteroscopic procedure (polypectomy)[65]. This outpatient surgery is quick, effective, and relieves symptoms in the vast majority of cases[66]. The removed tissue is examined to ensure it’s benign.
• Outlook: After removal, polyps rarely recur[68]. Most women return to regular menstrual patterns and improved fertility if that was affected. Only a very small number of polyps have any cancerous potential, and removing them essentially cures the issue.
• Always follow up with your healthcare provider for abnormal bleeding. Endometrial polyps are one common cause, but your doctor will make sure to rule out other conditions. With proper care, you can keep your uterus healthy and address any polyps with confidence.

FAQs about Endometrial Polyps

Are endometrial polyps cancerous?

In the vast majority of cases, no, endometrial polyps are not cancerous. Approximately 95% of endometrial polyps are benign (noncancerous)[41]. About 5% or fewer may contain abnormal (precancerous or cancerous) cells. Factors that slightly increase the chance of a polyp being cancerous include being over age 50 and having postmenopausal bleeding due to the polyp[41]. Because of this small potential risk, doctors usually send any removed polyp to a lab for analysis. If a polyp does have atypical or cancerous cells, the treatment plan might be adjusted (for example, further surgery to ensure all abnormal tissue is gone). But remember: the odds are strongly in favor of it being benign. Polyps are a common benign reason for irregular bleeding.

Can endometrial polyps affect fertility or pregnancy?

Endometrial polyps have been associated with infertility or difficulty getting pregnant. A polyp can act like a foreign body in the uterus, potentially interfering with embryo implantation. Many fertility doctors will recommend removing a known polyp if a woman is trying to conceive, especially if she has experienced miscarriages[70]. The good news is that removing the polyp often improves the uterine environment. While research is still ongoing, some studies suggest that fertility outcomes improve after polyp removal (with higher pregnancy rates compared to before removal). It’s important to note that not all women with polyps experience infertility – many still get pregnant just fine. If you have a polyp and are planning a pregnancy, discuss with your doctor whether removal could be beneficial for you. Also, current evidence doesn’t strongly link polyps to causing miscarriage; earlier thinking suspected a connection, but newer studies indicate polyps are not a major cause of miscarriage[70]. Nonetheless, because polyps can be easily removed, it’s often done proactively in the infertility work-up.

What is the difference between an endometrial polyp and a fibroid?

This is a great question, as polyps and fibroids are both common uterine growths but are quite different in nature: – An endometrial polyp arises from the endometrium (uterine lining). It’s basically an overgrowth of the lining tissue. Polyps only form within the uterine cavity (interior) because that’s where the lining is[71]. – A fibroid (also called a leiomyoma) is a benign tumor of the uterine muscle wall. Fibroids originate from the muscular layer of the uterus and can grow in various locations: inside the cavity (submucosal fibroid), within the wall (intramural fibroid), or on the outer surface of the uterus (subserosal fibroid). – Polyps tend to be soft, fleshy, and small. Fibroids are usually firmer (made of muscle and fibrous tissue) and can grow much larger – from pea-size to grapefruit-size or beyond. – Symptom-wise, both can cause heavy or irregular bleeding. Fibroids, especially larger ones, are more likely to cause pain, pressure, or bulk symptoms (like bladder pressure or a visible abdominal bulge), whereas polyps usually don’t cause pain[50]. – Cancer risk: Endometrial polyps carry a small risk (~5%) of containing precancerous or cancerous cells[41]. Uterine fibroids almost never turn cancerous (less than 1% chance, and those are a different type of tumor, not a typical fibroid)[71]. In other words, fibroids are even less often associated with cancer than polyps. – From a treatment perspective, polyps are removed via hysteroscopic polypectomy. Fibroids might require different treatments (medication, myomectomy, etc.) depending on size and location.

Sometimes both can occur together. But knowing which one you have is important for proper management. A doctor can usually distinguish between them with imaging (ultrasound, etc.) or during a hysteroscopy.

How are endometrial polyps removed, and is it painful?

Endometrial polyps are typically removed via a procedure called hysteroscopic polypectomy. Here’s what to expect: – It’s often done as an outpatient procedure. You might receive local anesthesia, conscious sedation, or light general anesthesia – so you stay comfortable and pain-free. – The doctor inserts a hysteroscope (a thin camera) through the vagina and cervix into the uterus to directly see the polyp[72]. There are no external incisions. – Tiny instruments (like scissors or a wire loop) are fed through the scope to cut out and remove the polyp[72]. The process is fairly quick, often just minutes once the scope is in place. – You shouldn’t feel pain during the removal due to anesthesia. You may feel some cramping or pressure, but it’s usually mild. – After the procedure, it’s common to have light cramping and a bit of spotting for a few days. Over-the-counter pain relievers are generally enough to handle any discomfort. – Most people are back to normal activities within a day or two. Since there’s no cut on your abdomen, recovery is much easier than with surgeries that have incisions. – The polyp tissue is sent to a lab to be analyzed, which is standard protocol.

Overall, hysteroscopic removal of a polyp is a quick and relatively low-pain procedure. Patients often report that the worst part is like mild period cramps afterwards. If your doctor suggests polyp removal, you can feel reassured that it’s a routine procedure with a high success rate in resolving symptoms.