Postmenopausal bleeding: why this one always gets investigated

The rule, stated plainly

Any vaginal bleeding after twelve consecutive months without a period should be assessed. This includes a single episode, a pink or brown smear, spotting seen only on wiping, and bleeding that stops on its own before the appointment.

It applies whether or not you take hormone therapy, though the interpretation differs and is covered below.

There is no version of this where waiting to see if it happens again is the right approach.

What it usually turns out to be

The most common causes are benign, and knowing them is useful for keeping the fear proportionate while still getting seen:

• Atrophy of the womb lining or the vaginal tissue — thin, fragile tissue that bleeds easily. The single most common cause
• Endometrial or cervical polyps, benign growths that bleed
• Effects of hormone therapy, particularly in the first months or with an irregular regimen
• Infection or inflammation of the cervix or vagina
• Endometrial hyperplasia, a thickened lining that can be a precursor to cancer and is treatable
• Endometrial cancer, in roughly 8 to 10% of cases

What the investigation involves

The first step is usually a transvaginal ultrasound to measure the thickness of the womb lining. A thin lining makes cancer very unlikely and often ends the investigation there.

If the lining is thickened, or if bleeding continues despite a reassuring scan, the next step is a sample of the lining — an endometrial biopsy, usually taken in clinic, sometimes with a hysteroscopy that allows the cavity to be seen directly.

Many health systems have a fast-track pathway for this symptom, typically aiming to see people within two weeks. It is reasonable to ask whether you are on it.

If you are on hormone therapy

Breakthrough bleeding is common in the first three to six months of hormone therapy and with sequential regimens it is expected on a predictable monthly schedule.

What still needs reporting: bleeding that starts after six months of settled treatment, bleeding that changes pattern, bleeding that is heavy, and any bleeding outside the expected window on a sequential regimen.

Being on hormone therapy is an explanation to be confirmed, not a reason to skip the assessment.

When to see someone

Promptly, for any bleeding at all after twelve months without a period. Say the words postmenopausal bleeding when you book, because it changes how quickly you are seen.

Mention any hormone therapy, tamoxifen use, or a family history of endometrial, ovarian or bowel cancer, all of which affect the assessment.