What is Human Chorionic Gonadotropin?

By Medically reviewed by hellodoktor

Know the basics

What is Human Chorionic Gonadotropin?

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 and some just check to see if the hormone is present. HCG is made by the placenta during pregnancy. The hCG test can be used to see if a woman is pregnant or as part of a screening test for birth defects.

HCG may also be made abnormally by certain tumors, especially those that come from an egg or sperm (germ cell tumors). HCG levels are often tested in a woman who may have abnormal tissue growing in her uterus, a molar pregnancy, or a cancer in the uterus (choriocarcinoma) rather than a normal pregnancy. Several hCG tests may be done after a miscarriage to be sure a molar pregnancy is not present. In a man, hCG levels may be measured to help see whether he has cancer of the testicles.

HCG in pregnancy

An egg is normally fertilized by a sperm cell in a fallopian tube camera.gif. Within 9 days after fertilization camera.gif, the fertilized egg moves down the fallopian tube into the uterus and attaches (implants) to the uterine wall. Once the fertilized egg implants, the developing placenta begins releasing hCG into your blood. Some hCG also gets passed in your urine. HCG can be found in the blood before the first missed menstrual period, as early as 6 days after implantation.

HCG helps to maintain your pregnancy and affects the development of your baby (fetus). Levels of hCG increase steadily in the first 14 to 16 weeks following your last menstrual period (LMP), peak around the 14th week following your LMP, and then decrease gradually. The amount that hCG increases 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.

More hCG is released in a multiple pregnancy, such as twins or triplets, than in a single pregnancy. Less hCG is released if the fertilized egg implants in a place other than the uterus, such as in a fallopian tube. This is called an ectopic pregnancy.

Why is Human Chorionic Gonadotropin performed?

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

  • See whether you are pregnant.
  • Find an ectopic pregnancy.
  • Find and check the treatment of a molar pregnancy.
  • See whether there is an increased chance of birth defects such as Down syndrome. The test is used in combination with other screening tests.
  • Find and check 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.

Things to know before

What should I know before receiving Human Chorionic Gonadotropin?

A blood test for hCG is generally more accurate than a urine test. If pregnancy is suspected even after urine test results do not show a pregnancy (negative results), a blood test can be done, or another urine test should be repeated in a week.

HCG results may remain high (positive) for up to 4 weeks after a miscarriage (spontaneous abortion) or therapeutic abortion.

A normal hCG value does not rule out the possibility of a tumor in the uterus, ovaries, or testicles. HCG is only one part of an overall evaluation when a tumor is suspected.

The level of hCG in the blood is often used in a maternal serum triple or quadruple screening test.

Know what happens

How to prepare for Human Chorionic Gonadotropin?

If a blood sample is collected, you do not need to do anything before you have this test.

If a urine test is done, the first urine of the day is generally the best to use because it has the highest level of hCG. A urine sample collected at least 4 hours after the last urination will also have high amounts of hCG.

What happens during Human Chorionic Gonadotropin?

Human chorionic gonadotropin (hCG) may be measured in a sample of blood or urine.

Blood sample collection

Your doctor will clean a small area of your arm or elbow with an antiseptic wipe or alcohol pad. In some cases, he or she will wrap an elastic band around the top of your arm to increase the flow of blood. This makes collecting blood from your veins much easier.

Your arm will then be pricked with a needle that the doctor then inserts into your vein. A tube that will collect blood is attached to the other end of the needle.

Once enough blood is drawn, the doctor will remove the needle. He or she will then apply a cotton swab and bandage to stop any bleeding where the needle punctured your skin.

Urine collection

If possible, collect a sample from the first urine of the day (this urine generally has the highest level of hCG). A urine sample collected at least 4 hours after the last urination will also have high amounts of hCG.

Place the collection container into the stream of urine, and collect about 4 Tbsp (60 mL) of urine.

Do not touch the rim of the container to your genital area, and do not get toilet paper, pubic hair, stool (feces), blood, or other foreign matter in the urine sample.

Finish urinating into the toilet or urinal.

Carefully replace the lid on the container, and return it to the lab. If you are collecting the urine at home and cannot get it to the lab in an hour, refrigerate it.

What happens after Human Chorionic Gonadotropin?

You will be dated to get the results of your test. Your doctor will explain what your test results mean for you. You should follow the instructions of your doctor.

Understand the results

What do my results mean?

Normal

The normal values listed here—called a reference range—are just a guide. These ranges vary from lab to lab, and your lab may have a different range for what’s normal. Your lab report should contain the range your lab uses. Also, your doctor will evaluate your results based on your health and other factors. This means that a value that falls outside the normal values listed here may still be normal for you or your lab.

Human chorionic gonadotropin (hCG) levels in blood
Men and nonpregnant women: Less than 5 international units per liter (IU/L)
Pregnant women, 1 week of gestation (about 3 weeks after the last menstrual period): 5–50 IU/L
Pregnant women, 2 weeks of gestation (about 4 weeks after the LMP): 50–500 IU/L
Pregnant women, 3 weeks of gestation (about 5 weeks after the LMP): 100–10,000 IU/L
Pregnant women, 4 weeks of gestation (about 6 weeks after the LMP): 1080–30,000 IU/L
Pregnant women, 6–8 weeks of gestation (about 8–10 weeks after the LMP): 3500–115,000 IU/L
Pregnant women, 12 weeks of gestation (about 14 weeks after the LMP): 12,000–270,000 IU/L
Pregnant women, 13–16 weeks of gestation (about 15–18 weeks after the LMP): Up to 200,000 IU/L
hCG levels in urine
Men: None (negative test)
Nonpregnant women: None (negative test)
Pregnant women: Detectable (positive test

High values

If you are pregnant, very high levels of human chorionic gonadotropin (hCG) can mean a multiple pregnancy (such as twins or triplets), a molar pregnancy, Down syndrome, or that you are further along in an early pregnancy than estimated by your last menstrual period (LMP).

In a man or a nonpregnant woman, a high hCG level can mean a tumor (cancerous or noncancerous) that develops from a sperm or egg cell (germ cell tumor), such as a tumor of the testicles or ovaries, is present. It may also mean some types of cancer, such as cancer of the stomach, pancreas  , large intestine, liver, or lung.

Low values

If you are pregnant, low levels of hCG can mean an ectopic pregnancy, death of your baby, or that you are not as far along in an early pregnancy as estimated by your last menstrual period (LMP).

If you are pregnant, levels of hCG that are decreasing abnormally can mean a miscarriage (spontaneous abortion) is very likely.

Depending on the laboratory and hospital, the normal range for Human chorionic gonadotropin may vary. Please discuss with your doctor any questions you may have about your test results.

If you have any questions about the Human chorionic gonadotropin, please consult with your doctor to better understand your instructions.

Hello Health Group does not provide medical advice, diagnosis or treatment.

Review Date: May 30, 2016 | Last Modified: September 12, 2019

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