Human Chorionic Gonadotropin (HCG) Test

Test Overview

The human chorionic gonadotropin (hCG) test is done to check for the hormone hCG in blood or urine. Some hCG tests measure the exact amount. Some just check to see if the hormone is present. HCG is made by the placenta during pregnancy. The test can be used to see if a woman is pregnant. HCG can be found in the blood before the first missed menstrual period. This can be as early as 6 days after the egg implants.

The test can also be done as part of a screening test for birth defects. The amount that hCG goes up early in pregnancy can give information about your pregnancy and the health of your baby. Soon after delivery, hCG can no longer be found in your blood.

HCG may also be made by certain tumors, especially those that come from an egg or sperm. (These are called germ cell tumors.) HCG levels are often tested in a woman who may have tissue that is not normal growing in her uterus. The test also may be done to look for molar pregnancy or a cancer inside the uterus. In a man, hCG levels may be measured to help see if he has cancer of the testicles.

Why It Is Done

A test for human chorionic gonadotropin (hCG) is done to:

• See if you are pregnant.
• Find an ectopic pregnancy.
• Check the treatment of a molar pregnancy.
• See if there is a greater chance of birth defects such as Down syndrome. The test is done with other screening tests.
• Find and check on the treatment of a cancer that develops from an egg or sperm (germ cell cancer), such as cancer of the ovaries or testicles. In such cases, a test for alpha-fetoprotein may be done along with a test for hCG.

How To Prepare

In general, there's nothing you have to do before this test, unless your doctor tells you to.

How It Is Done

A urine or blood test for pregnancy can be done in your doctor's office, clinic, or lab.

Blood test

A health professional uses a needle to take a blood sample, usually from the arm.

Urine test

You catch urine in a cup given to you by a health professional. When you are finished, you give the cup back.

How long the test takes

The test will take just a few minutes.

How It Feels

Blood test

When a blood sample is taken, you may feel nothing at all from the needle. Or you might feel a quick sting or pinch.

Urine test

In most cases, there is no pain with collecting a urine sample.

Risks

Blood test

There is very little chance of having a problem from this test. When a blood sample is taken, a small bruise may form at the site.

Urine test

Collecting a urine sample does not cause problems.

Results

Each lab has a different range for what's normal. Your lab report should show the range that your lab uses for each test. The normal range is just a guide. Your doctor will also look at your results based on your age, health, and other factors. A value that isn't in the normal range may still be normal for you.

High values

Low values

• If you are pregnant, a low level of hCG can mean an ectopic pregnancy or a miscarriage. It may also mean that you aren't as far along in an early pregnancy as you thought, based on your last menstrual period (LMP).
• If you are pregnant, levels of hCG that are going down abnormally can mean that a miscarriage (spontaneous abortion) is very likely.