Patient education: hCG blood test (The Basics)

What is an hCG blood test? — 

This measures the amount of human chorionic gonadotropin, or "hCG," in the blood. hCG is a hormone that is normally made by the placenta during pregnancy. The placenta is the organ that forms between a pregnant person and their baby (figure 1).

hCG is important during pregnancy to:

●Thicken the lining of the uterus (figure 2)

●Stop menstruation – This is the medical term for having a period.

hCG can also be produced by some cancers.

hCG testing can also be done with a urine test.

Why might I get an hCG blood test? — 

Your doctor might order this test:

●To check if you are pregnant – Your doctor or nurse can take a blood sample to test it in a lab.

●If you know you are pregnant and:

•Your doctor wants to monitor the pregnancy – To do this, they can check your hCG level to see how it changes over time. This might be done if:

-You got pregnant through in vitro fertilization, or "IVF."

-Your doctor is concerned about certain problems – These might include a pregnancy loss (miscarriage) or an ectopic pregnancy. An ectopic pregnancy is a pregnancy that is located outside of the uterus.

•You are having a "screening" test – This can be done early in pregnancy to find out whether your baby is likely to have certain genetic disorders, like Down syndrome. This is done with lab tests and an ultrasound.

●If you had a pregnancy loss, ectopic pregnancy, or abortion – Your doctor might check your hCG level to confirm you are no longer pregnant.

●To check for or monitor certain kinds of tumors that produce hCG

How do I prepare for an hCG test? — 

For this test, you need to get a "blood draw." Your doctor or nurse will tell you where to go for this.

It might help to wear a short-sleeve shirt to your blood draw appointment. This makes it easier for the person drawing your blood to get to your arm.

What happens during a blood draw? — 

A needle is used to take a small amount of blood from your arm (figure 3). Collecting the blood only takes a few minutes. The blood is then tested in a lab.

Tell the person who takes your blood:

●If you take "blood thinner" medicines or if you have a bleeding problem – They will make sure your bleeding is under control before you leave.

●If you have a latex allergy – Some of the supplies used for blood draws might contain latex.

●If you have a preferred arm to use

Most of the time, getting blood taken does not cause problems. You might have a little soreness or bruising where the needle went in.

What do my results mean? — 

Your doctor or nurse will tell you when to expect your results, and will contact you with the results. Or if you use an online "patient portal," you might get an alert there when your results are ready.

Your doctor or nurse will talk to you about what to do next if your hCG test shows:

●You are pregnant

●Any abnormal results – You might need more tests to figure out what the cause is.

Your doctor might need to repeat the hCG test several times to see how your level changes over time.

If you have a health problem, your doctor will work with you to come up with a plan for treatment.

More on this topic

Patient education: Pregnancy tests (The Basics)
Patient education: Bleeding in early pregnancy (The Basics)
Patient education: Pregnancy loss (The Basics)
Patient education: Ectopic pregnancy (The Basics)
Patient education: Testing for Down syndrome during pregnancy (The Basics)

Patient education: Pregnancy loss (Beyond the Basics)
Patient education: Ectopic (tubal) pregnancy (Beyond the Basics)
Patient education: Should I have a screening test for Down syndrome during pregnancy? (Beyond the Basics)