Endometrial Polyps

What are endometrial polyps?

Endometrial polyps are growths that form on the inner lining of the uterus (endometrium). These are typically benign (non-cancerous) projections of endometrial tissue, which may be attached to the uterine wall by a thin stalk (pedunculated) or a broad base (sessile). They vary in size, ranging from a few millimetres to several centimetres, and may occur as single or multiple polyps.

These polyps are composed of endometrial glands, stroma (connective tissue), and blood vessels. While many women with endometrial polyps remain asymptomatic, others may experience symptoms such as irregular menstrual bleeding, intermenstrual spotting, heavy periods (menorrhagia), or bleeding after menopause. In some cases, endometrial polyps may also be linked to difficulties with fertility or failed IVF cycles.

Endometrial polyps are most commonly found in women aged between 40 and 50 years, though they can occur at any age. They are hormone-sensitive, with oestrogen playing a key role in their development. As such, polyps are more likely to develop in women with high levels of circulating oestrogen, such as those undergoing hormone replacement therapy (HRT) or taking medications like tamoxifen.

Although the majority of endometrial polyps are benign, a small percentage may show precancerous changes or contain malignant cells, particularly in postmenopausal women or those with risk factors. For this reason, proper assessment and removal are often advised, especially when symptoms are present or the woman is at increased risk for endometrial cancer.

What causes endometrial polyps? 

The exact cause of endometrial polyps is not fully understood, but their development is closely linked to hormonal factors, particularly oestrogen. These growths tend to arise when the endometrial lining is exposed to prolonged or unopposed oestrogen stimulation, which leads to localised overgrowth of the endometrial tissue.

Several factors may contribute to the formation of endometrial polyps:

• Hormonal imbalance — Oestrogen stimulates the endometrium to grow, and when this effect is not adequately counteracted by progesterone, it can promote the development of polyps. This is particularly relevant in conditions like anovulation, polycystic ovary syndrome (PCOS), or perimenopause, where hormonal fluctuations are common.

• Age and menopausal status — polyps are more frequently diagnosed in women aged 40–50 and in those approaching or after menopause. Despite the natural decline in oestrogen post-menopause, some women continue to produce low levels of oestrogen sufficient to maintain or promote polyp formation.

• Obesity — excess adipose tissue can convert androgens into oestrogens, leading to higher circulating levels of oestrogen in the body and increased risk of endometrial hyperplasia and polyps.

• Medications — certain drugs, such as tamoxifen (commonly used in breast cancer treatment), have a partial oestrogen-like effect on the uterus and are associated with a higher risk of developing endometrial polyps.

• Hormone replacement therapy (HRT) — women receiving oestrogen-only HRT, particularly without the addition of progesterone, may be at higher risk.

• Hypertension and other metabolic conditions — some studies have observed a correlation between endometrial polyps and systemic conditions such as high blood pressure or insulin resistance, although these associations are still being investigated.

While these risk factors may contribute to polyp development, many women diagnosed with endometrial polyps do not have any identifiable risk factor. Understanding the hormonal influence, however, remains key to both prevention and management.

What are the symptoms of endometrial polyps? 

Endometrial polyps often cause no symptoms and are discovered incidentally during investigations for unrelated issues or during routine gynaecological scans. However, when symptoms do occur, they are usually related to abnormal patterns of uterine bleeding.

Common symptoms include:

• Irregular menstrual bleeding — this may involve unpredictable timing or duration of periods, with some women experiencing spotting between cycles or a complete change in their usual menstrual pattern.

• Intermenstrual bleeding — light bleeding or spotting between otherwise regular periods can be an early indicator of an endometrial polyp.

• Heavy menstrual bleeding (menorrhagia) — some women may report unusually heavy or prolonged periods due to the presence of polyps disrupting the normal endometrial shedding.

• Postmenopausal bleeding — any vaginal bleeding after menopause is considered abnormal and warrants evaluation. Endometrial polyps are one of the possible causes and must be ruled out or confirmed.

• Bleeding after intercourse — in certain cases, contact during sexual activity may irritate the polyp and trigger bleeding.

• Infertility or difficulty conceiving — although not all polyps affect fertility, large or strategically located polyps may interfere with implantation or disrupt the endometrial environment.

It is important to note that the severity of symptoms does not always correlate with the size or number of polyps. Even small polyps may cause significant bleeding if they are located near sensitive areas of the uterine lining.

Any abnormal bleeding, particularly in postmenopausal women or those trying to conceive, should be assessed by a gynaecologist to rule out serious conditions and to determine whether a polyp or another underlying issue is responsible.

Who is at risk of endometrial polyps in Singapore? 

Endometrial polyps can occur in women of any age, but certain groups are more likely to develop them due to hormonal influences and underlying health conditions. 

Women may be at increased risk if they:

• Are in their 40s or 50s — endometrial polyps are most commonly diagnosed in women during perimenopause and early postmenopause, a time when hormonal fluctuations are common and unopposed oestrogen activity may lead to abnormal endometrial growth.

• Have obesity or overweight — excess fat tissue contributes to higher oestrogen levels in the body, which can stimulate the endometrial lining and increase the risk of polyps.

• Experience irregular ovulation — conditions like polycystic ovary syndrome (PCOS) or thyroid disorders, which interfere with regular ovulation, may cause prolonged oestrogen exposure without the balancing effect of progesterone.

• Are on hormone replacement therapy (HRT) — particularly oestrogen-only HRT regimens may increase the risk if not balanced with progesterone.

• Have a family history of uterine or endometrial conditions — while not strongly hereditary, a family tendency towards gynaecological abnormalities may contribute to increased vigilance and earlier detection.

Although these factors raise the likelihood of developing endometrial polyps, they can also appear in women with no obvious risk profile. As such, any abnormal uterine bleeding or fertility issue should be evaluated thoroughly, regardless of age or medical history.

How are endometrial polyps diagnosed? 

Diagnosing endometrial polyps typically involves a combination of clinical history, pelvic examination, and imaging studies. Because polyps often cause abnormal uterine bleeding or are found during fertility investigations, evaluation usually begins when symptoms prompt further assessment.

Common diagnostic methods include:

• Transvaginal ultrasound — this is the primary imaging technique used to visualise the uterus. A thin ultrasound probe is inserted into the vagina to provide high-resolution images of the endometrial lining. Polyps may appear as localised thickening or well-defined masses within the endometrium. In some cases, saline may be introduced into the uterus (saline infusion sonography) to better outline the polyp.

• Saline infusion sonography (SIS) — also known as sonohysterography, this procedure involves gently introducing sterile saline into the uterus during transvaginal ultrasound. The fluid distends the uterine cavity, which improves visual contrast and allows more accurate identification of polyps and their size or attachment.

• Hysteroscopy — Hysteroscopy is another common method used for diagnosing and treating endometrial polyps. A thin telescope-like instrument is inserted through the cervix into the uterus, allowing direct visual inspection of the endometrial cavity. Polyps can be clearly seen, and in many cases, removed during the same procedure (operative hysteroscopy).

• Endometrial biopsy — a small sample of the endometrial tissue may be taken for histological examination. While this may not always detect a polyp (especially if it is small or missed by the sampling instrument), it can help rule out other causes of abnormal bleeding, including precancerous changes or malignancy.

What are the treatment options for endometrial polyps in Singapore? 

The treatment of endometrial polyps depends on several factors, including the patient’s age, symptoms, risk of malignancy, and whether fertility is a concern. While some polyps may not require immediate intervention, others warrant removal to relieve symptoms or exclude cancer.

Common treatment approaches include:

• Observation — in asymptomatic, premenopausal women with small polyps, especially those discovered incidentally, a conservative approach may be taken. Regular monitoring with ultrasound may be recommended, particularly if there are no risk factors for cancer.

• Hysteroscopic polypectomy — this is the most commonly used method for removing endometrial polyps. It involves inserting a hysteroscope through the cervix into the uterus to directly visualise and remove the polyp, often in a day surgery setting. The removed tissue is then sent for histopathological analysis to confirm its nature.

• Curettage (D&C) — dilation and curettage may be used in settings where hysteroscopy is not available, although it is less precise. This involves scraping the uterine lining to remove the polyp, but small or sessile polyps may be missed without visual guidance.

• Medical management — hormonal treatments such as progestins or gonadotropin-releasing hormone (GnRH) agonists may help control symptoms like abnormal bleeding, but they do not reliably eliminate polyps. Medications are sometimes used temporarily or in patients who are unfit for surgery.

• Treatment in postmenopausal women — due to the slightly increased risk of malignancy in this group, removal is generally recommended even for asymptomatic polyps. Hysteroscopic removal followed by histological assessment is the common treatment option used in this case. 

Recurrence of polyps can occur, particularly in women with underlying hormonal imbalances or those taking medications like tamoxifen. Regular follow-up may be advised depending on individual risk factors.

What is recovery like after treatment for endometrial polyps? 

Recovery after treatment for endometrial polyps, particularly following hysteroscopic polypectomy, is usually straightforward, with most women able to resume normal activities within a day or two. The procedure is commonly performed as a day surgery, under light sedation or general anaesthesia, and does not typically require hospital admission.

Common post-procedure experiences include:

• Mild cramping or discomfort — this may feel similar to period pain and usually settles within a few hours to a couple of days. Over-the-counter pain relief is often sufficient.

• Light vaginal bleeding or spotting — some bleeding is expected for a few days following removal. Women are usually advised to avoid using tampons or having intercourse for around one to two weeks, or until bleeding stops, to reduce the risk of infection.

• Prompt return to daily routines — most women can go back to work and normal activities within 24–48 hours, although it is best to avoid strenuous exercise for a few days.

• Follow-up care — histological results from the removed polyp are typically reviewed at a follow-up appointment. In some cases, further monitoring or treatment may be advised, particularly if atypical or pre-cancerous cells were detected.

For women trying to conceive, fertility may improve after polyp removal, particularly if the polyp was interfering with implantation. Your gynaecologist may advise a timeline for attempting pregnancy or planning fertility treatments following recovery.

Overall, recovery is quick for most, and complications are rare when the procedure is performed by an experienced specialist.

Summary 

Endometrial polyps are common, often benign growths in the uterine lining that may cause abnormal bleeding, fertility issues, or remain completely asymptomatic. While their exact cause is not always clear, hormonal imbalances, especially unopposed oestrogen, play a key role. Risk factors include age, obesity, certain medications like tamoxifen, and conditions such as PCOS. 

Diagnosis is usually made through transvaginal ultrasound or hysteroscopy, which also allows for direct removal. Treatment depends on symptoms, risk factors, and fertility goals, with hysteroscopic polypectomy being the most common and precise option. Recovery is typically quick, with most women returning to normal activities within days. 

If you are experiencing irregular bleeding, trying to conceive without success, or have concerns about uterine health, schedule a consultation with Holistic Gynaecology & Fertility for a comprehensive assessment and personalised care.

Frequently Asked Questions (FAQs)