Given that any postmenopausal bleeding warrants assessment, the diagnostic pathway is typically structured to efficiently identify the cause and rule out serious conditions. The initial assessment usually involves a detailed medical history and a physical examination, including a pelvic exam to check for vaginal or cervical sources of bleeding. This comprehensive approach ensures that all potential causes are considered.

Initial Clinical Assessment

Upon presentation with PMB, your healthcare provider will first take a detailed medical history. This includes questions about:

• The nature of the bleeding (e.g., spotting, heavy, intermittent, post-coital)
• Duration and frequency of bleeding episodes
• Any associated symptoms (pain, discharge, urinary changes)
• Current and past medication use, including HRT, anticoagulants, and tamoxifen
• Personal and family history of gynaecological cancers
• Other medical conditions (e.g., obesity, diabetes, hypertension)

A physical examination will follow, which typically includes a speculum examination to visualise the cervix and vagina, and a bimanual examination to assess the uterus and ovaries. This helps to identify obvious sources of bleeding, such as cervical polyps, vaginal lesions, or signs of severe atrophy.

The Role of Transvaginal Ultrasound (TV US)

Transvaginal ultrasound (TV US) is often the first-line investigation for postmenopausal bleeding. This non-invasive imaging technique provides detailed views of the uterus, ovaries, and surrounding pelvic structures. It is particularly effective for assessing the endometrial thickness, which is a crucial triage tool and a cornerstone of PMB investigation [4].

• Endometrial Thickness Measurement: A key parameter measured during TV US is the endometrial thickness. In postmenopausal women not on HRT, an endometrial thickness of ≤4mm is generally considered reassuring and indicates a very low risk of endometrial cancer (less than 1%) [4]. If the thickness is greater than 4mm, further investigation is usually recommended to definitively rule out hyperplasia or malignancy. For women on HRT, the endometrial thickness cut-off may vary depending on the type of HRT, but any unexpected bleeding warrants investigation regardless of thickness.
• Detection of Polyps and Fibroids: TV US can also identify endometrial polyps, uterine fibroids, and other structural abnormalities that might be contributing to the bleeding. The use of colour Doppler can help assess the blood flow to these structures, providing further diagnostic clues and helping to differentiate benign from potentially malignant lesions.
• Ovarian Assessment: The ovaries are also visualised during the scan to check for any abnormalities, such as cysts or solid masses, which could be an indirect cause of bleeding (e.g., oestrogen-secreting tumours) or a separate concern requiring further evaluation.

Further Diagnostic Steps

If the TV US reveals an endometrial thickness greater than 4mm, if the lining cannot be adequately visualised, or if there are other suspicious findings or persistent bleeding despite a thin lining, additional procedures are necessary. These steps are designed to obtain tissue samples for histological analysis, which is the gold standard for diagnosing endometrial pathology.

• Endometrial Biopsy: This is often the next step. A thin, flexible tube (Pipelle catheter) is passed through the cervix into the uterus to take a small sample of the endometrial lining. This sample is sent to a laboratory for histological examination under a microscope. This is the definitive way to diagnose endometrial hyperplasia or cancer. It can often be done in an outpatient setting with minimal discomfort.
• Hysteroscopy with Biopsy: If a biopsy is inconclusive, or if a focal lesion like a polyp or submucosal fibroid is suspected, a hysteroscopy may be performed. This involves passing a thin, lighted telescope (hysteroscope) through the cervix to directly visualise the inside of the uterus. It allows for targeted biopsies from suspicious areas and the removal of polyps or small fibroids during the same procedure. Hysteroscopy provides a direct visual assessment that blind biopsies may miss.
• Saline Infusion Sonography (SIS): Also known as a sonohysterogram, this involves introducing sterile saline into the uterus during an ultrasound. The fluid distends the uterine cavity, providing excellent contrast and allowing for better visualisation of focal lesions like polyps or submucosal fibroids that might be missed on a standard TV US. SIS is particularly useful for distinguishing diffuse endometrial thickening from focal lesions.

Management Approaches and What Happens Next

Treatment for PMB depends entirely on the underlying cause identified through the diagnostic pathway. A tailored approach ensures the most effective and appropriate care.

• Endometrial or Vaginal Atrophy: If atrophy is confirmed as the cause, management often involves reassurance and education about the benign nature of the condition. If symptoms like dryness, discomfort, or recurrent spotting are bothersome, topical vaginal oestrogen (creams, pessaries, or rings) can be highly effective in restoring the tissue integrity and stopping the bleeding. Non-hormonal moisturisers and lubricants can also help alleviate symptoms. Lifestyle modifications, such as avoiding irritants, may also be recommended.
• Endometrial Polyps: Polyps are typically removed via hysteroscopy (polypectomy). This procedure is usually curative, resolves the bleeding, and allows the tissue to be examined by a pathologist to confirm it is benign. Recurrence is possible, and follow-up may be advised.
• Endometrial Hyperplasia: Management depends on whether atypical cells are present. Hyperplasia without atypia is often treated with progestogen therapy (e.g., an intrauterine system like Mirena or oral tablets) to thin the lining and reverse the hyperplasia. Regular follow-up biopsies are crucial to monitor treatment response. Atypical hyperplasia carries a higher risk of progressing to cancer and is often treated with a hysterectomy, especially in postmenopausal women, or high-dose progestogen therapy with very close surveillance for those wishing to preserve fertility (a rare consideration in PMB).
• Endometrial Cancer: If cancer is diagnosed, the primary treatment is usually surgery, typically a total hysterectomy with removal of the ovaries and fallopian tubes (bilateral salpingo-oophorectomy). Depending on the stage and grade of the cancer, further treatment such as radiotherapy, chemotherapy, or targeted therapy may be recommended. Early-stage endometrial cancer has a very good prognosis, highlighting the importance of prompt investigation of PMB.
• Other Causes: Management of other causes, such as cervical polyps or fibroids, will depend on their specific characteristics and the patient's symptoms. Cervical polyps can often be removed in an outpatient setting. Symptomatic fibroids may require myomectomy or hysterectomy, though conservative management is often preferred in asymptomatic cases.

The Importance of Follow-Up and Ongoing Care

Regardless of the initial diagnosis, follow-up is crucial. If you have been diagnosed with a benign condition like atrophy but the bleeding recurs or persists after treatment, you must seek medical attention again. A thin endometrium on an initial scan is reassuring, but it does not guarantee that pathology will not develop later. Always report any new or recurrent episodes of postmenopausal bleeding to your healthcare provider. Regular gynaecological check-ups are also important for ongoing women's health.