Womb (Endometrial) Cancer: Signs and Risk Factors

TL;DR: The most common sign of womb (endometrial) cancer is abnormal vaginal bleeding, especially any bleeding after the menopause. Other signs include unusually heavy periods, bleeding between periods and a change in discharge. Being overweight, PCOS, oestrogen-only HRT, tamoxifen and Lynch syndrome all raise risk. Caught early, more than 90% of women survive five years or more, so get any unusual bleeding checked promptly.

Your periods stopped a couple of years ago. Then one morning there is a spot of blood. It is light, it does not hurt, and an auntie tells you it is probably "old blood" clearing out. Or you are in your forties, your periods have become heavier and messier than ever, and you put it down to perimenopause. Most of the time, these changes do turn out to be something minor. But bleeding that is new or unusual for you is the most common sign of womb cancer, and it often appears while the cancer is still at an early stage. That is good news, if you act on it.

What is womb cancer?

Womb cancer starts in the womb, also called the uterus. The NHS explains that most womb cancer starts in the lining of the womb, the endometrium, which is why you will also hear it called endometrial cancer. The NHS also notes it is most common in women who have been through the menopause, though it can happen earlier.

What are the signs of womb cancer?

The main symptom is abnormal bleeding. The NHS lists bleeding or spotting from the vagina after the menopause, heavy periods that are unusual for you, vaginal bleeding between your periods, and a change to your vaginal discharge. Cancer Research UK describes abnormal vaginal bleeding as the most common symptom, and notes the discharge can sometimes look pink.

Less common signs include a lump or swelling in your tummy or pelvis, lower back or pelvic pain, pain during sex, and needing to pee or poo more often than usual, according to the NHS. These symptoms have many other causes, and the NHS is clear that having them does not mean you have cancer. It does mean they deserve a check.

Is bleeding after menopause ever normal?

No. Any bleeding after you have gone 12 months without a period should be checked by a doctor, however light, and even if it only happens once. The NHS advises you to see a GP if you have any bleeding after the menopause. It is usually caused by something less serious, such as thinning of the vaginal lining or polyps, but it can be a sign of womb cancer, so it always needs looking at. Our post on periods in perimenopause explains how to tell the messy-but-normal changes from the ones to report.

UK guidance treats this seriously. NICE recommends that women aged 55 and over with unexplained post-menopausal bleeding that cannot be attributed to HRT are referred on a suspected cancer pathway, and that a referral is considered for women under 55 too. If you are on HRT and get unexpected bleeding, tell your prescriber rather than assuming it is a side effect.

Who is at higher risk?

Many womb cancer risk factors link back to oestrogen. When the womb lining is exposed to oestrogen without enough progesterone to balance it, the lining can keep thickening. The NHS lists these as factors that raise your risk:

• Being overweight. Cancer Research UK explains that fatty tissues produce more oestrogen, and estimates that being overweight or obese causes around a third of womb cancers.
• PCOS. With infrequent ovulation, the lining may build up without shedding regularly. Cancer Research UK says the higher risk may be linked to the hormone imbalance in PCOS and not only to weight. PCOS was renamed polyendocrine metabolic ovarian syndrome (PMOS) in 2026, and our PCOS guide explains why protecting the womb lining with regular bleeds matters.
• Oestrogen-only HRT if you still have a womb. Combined HRT includes a progestogen, which Cancer Research UK says counteracts the effects of the oestrogen on the lining. This is why anyone with a womb is offered combined HRT, as we explain in HRT benefits and risks.
• Tamoxifen. This breast cancer medicine can act like oestrogen on the womb. Cancer Research UK says the benefits for breast cancer outweigh this rare side effect, but report any bleeding if you take it.
• Lynch syndrome. This inherited condition raises the risk of several cancers. Cancer Research UK says up to 49 in 100 women with the gene fault will develop womb cancer at some point.
• Other factors. The NHS also lists diabetes, never having given birth, going through the menopause after 55, previous pelvic radiotherapy, and a family history of bowel, ovarian or womb cancer.

On the protective side, Cancer Research UK notes that taking the combined contraceptive pill lowers womb cancer risk, and the protection can continue for decades after stopping.

What about hair relaxers?

A large US study from the National Institutes of Health, published in the Journal of the National Cancer Institute, found that women who had used hair straighteners or relaxers in the previous year had higher rates of uterine cancer than women who had not, with a stronger link for frequent use. The authors called it the first evidence of this association and said more research is needed to confirm it and identify which chemicals might be involved. It shows a link, not proof of cause. We look at the wider research in hair relaxers and your health.

Do outcomes differ for Black women?

In the US, yes, and researchers are still working out why. National Cancer Institute data show that the uterine cancer death rate for non-Hispanic Black women is 9.9 per 100,000, about twice the rate of 4.9 per 100,000 for non-Hispanic White women. A National Cancer Institute study in JAMA Oncology found that rates of aggressive, non-endometrioid types of uterine cancer are disproportionately higher among Black women, and that the gap in deaths could not be fully explained by cancer type or stage at diagnosis.

These are US figures, and similar data for women across Africa and in the UK diaspora are more limited. The practical message is the same everywhere: if your bleeding pattern changes, do not let anyone, including you, explain it away. Our post on the health risks African women face covers more of this picture.

How is womb cancer diagnosed?

If your GP suspects womb cancer, the NHS says you may have a transvaginal ultrasound, where a small scanning probe is placed inside the vagina to look at the womb. You may also have a hysteroscopy, where a thin camera looks inside the womb, and a biopsy, where a small sample of the lining is taken to test. The NHS says these tests should not be painful, though some women find them uncomfortable, and you should get results within a few weeks.

If you are nervous about an internal scan or a hysteroscopy, you can ask about pain relief, ask for a chaperone, and ask the clinician to explain each step before it happens. Our guide to talking to your gynaecologist has tips for these conversations.

Why does catching it early matter?

Because womb cancer often causes bleeding early, many cases are found at an early stage, when treatment works best. In the US, 67% of uterine cancers are diagnosed while still localised. Cancer Research UK reports that in England, more than 90% of women diagnosed at stage 1 survive for five years or more, compared with 15% at stage 4. In the US, National Cancer Institute data show 94.9% five-year survival when the cancer is found while still localised, falling to 19.9% once it has spread to distant parts of the body.

When to see a doctor

See a GP or gynaecologist promptly if you have any bleeding after the menopause, bleeding between periods, periods that have become unusually heavy for you, or a new change in discharge. If you are bleeding very heavily, feel faint or breathless, or have severe pain, contact your nearest hospital emergency department. Our menopause guide has more on what is and is not expected in midlife.

Tracking makes these conversations easier. With Asele, cycle tracking and symptom logging help you record when bleeding happens and how heavy it is, even years after your periods stop. You can talk it through with Amara in Yoruba, Hausa, Igbo, Swahili, French or English, and the Health Brief gives you a short summary to take into your appointment. You can find us at Asele.

This post is education, not medical advice. Unusual bleeding is always worth a conversation with a clinician who can examine you.

References

1. NHS. Womb (uterus) cancer. nhs.uk
2. NHS. Symptoms of womb (uterus) cancer. nhs.uk
3. NHS. Causes of womb (uterus) cancer. nhs.uk
4. NHS. Tests and next steps for womb (uterus) cancer. nhs.uk
5. NHS. Postmenopausal bleeding. nhs.uk
6. NICE. Suspected cancer: recognition and referral (NG12), recommendations organised by site of cancer. nice.org.uk
7. Cancer Research UK. Symptoms of womb cancer. cancerresearchuk.org
8. Cancer Research UK. Risks and causes of womb cancer. cancerresearchuk.org
9. Cancer Research UK. Survival for womb cancer. cancerresearchuk.org
10. National Cancer Institute SEER. Cancer stat facts: uterine cancer. seer.cancer.gov
11. Clarke MA, et al. Racial and ethnic differences in hysterectomy-corrected uterine corpus cancer mortality by stage and histologic subtype. JAMA Oncology, 2022. pubmed.ncbi.nlm.nih.gov
12. Chang CJ, et al. Use of straighteners and other hair products and incident uterine cancer. Journal of the National Cancer Institute, 2022. pubmed.ncbi.nlm.nih.gov