Human chorionic gonadotropin (hCG or b-hCG)

Human chorionic gonadotropin (hCG or b-hCG) is a hormone that the placenta makes when a woman is pregnant. Certain cancer cells can also make it.

Why an hCG test is done

An hCG test may be done to:

  • confirm that you are pregnant
  • help diagnose some types of cancer and other conditions
  • find out if cancer treatment is working
  • watch for cancer coming back during follow-up care

How an hCG test is done

The amount of hCG is usually measured by a blood test taken by a needle in the arm. It can also be measured from a urine sample. You don’t need to do anything special to get ready for the test.

What the results mean

Your hCG levels may be higher than normal for many different reasons.

The level of hCG in your blood may be higher than normal because you are pregnant or you have a certain kind of bowel disease, a stomach ulcer or cirrhosis of the liver. Your HCG level can also be high if you smoke cannabis (marijuana).

An increased level of hCG in the blood may help your doctor diagnose:

  • gestational trophoblastic disease (GTD)
  • germ cell tumours of the ovary and testicle (both cancerous and non-cancerous tumours)

If you have liver, stomach, pancreatic, lung, breast or skin cancer, the level of hCG in your blood may be higher than normal.

The hCG test results can help your doctor know if treatment is working:

  • A decreased level or a return to normal levels of hCG may mean that the treatment is working.
  • An unchanged level of hCG or an increase in levels may mean that the cancer is not responding to treatment, is still growing or has come back (recurred).

What happens if the result is abnormal

Depending on the result, your doctor will decide if you need more tests, any treatment or follow-up care.

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