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. Or it can be done as part of a screening test for birth defects.
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. 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 if he has cancer of the testicles.
An egg is normally fertilized by a sperm cell in a fallopian tube. Within 9 days the fertilized egg moves down the fallopian tube into the uterus. It then attaches (implants) to the wall of the uterus. After the fertilized egg implants, the growing placenta starts 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. This can be as early as 6 days after the egg implants.
HCG helps to keep your pregnancy going. It also affects the development of your baby (fetus). Levels of hCG go up fast in the first 14 to 16 weeks after your last menstrual period. They are the highest around the 14th week following your last period. They then go down gradually. 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.
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.
The level of hCG in the blood is often used as part of a screening for birth defects in a maternal serum triple or quadruple screening test. These tests are usually done between 15 and 20 weeks of pregnancy to check the levels of three or four substances in a pregnant womans blood. The triple screen checks hCG, alpha-fetoprotein (AFP), and a type of estrogen (unconjugated estriol, or uE3). The quad screen checks these substances and the level of the hormone inhibin A. The levels of these substances-along with a womans age and other factors-help the doctor figure out the chance that the baby may have certain problems or birth defects.
In some cases, screening tests are combined in the first trimester to look for Down syndrome. This screening test uses an ultrasound to measure the thickness of the skin at the back of the fetuss neck (nuchal translucency). It also includes a blood test for the levels hCG and a protein called pregnancy-associated plasma protein A (PAPP-A). This test works about as well as the second-trimester maternal serum quad screening.footnote 1
HCG urine tests are usually used for regular pregnancy testing. The test does not measure the exact amount of hCG, but it shows if hCG is present. Home versions of this test are easy to find and buy.
A test for human chorionic gonadotropin (hCG) is done to:
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 you last urinated will also have high amounts of hCG.
Human chorionic gonadotropin (hCG) may be measured in a sample of blood or urine.
The health professional drawing blood will:
If possible, collect a sample from the first urine of the day.
The blood sample is taken from a vein in your arm. An elastic band is wrapped around your upper arm. It may feel tight. You may feel nothing at all from the needle, or you may feel a quick sting or pinch.
You may feel anxious while you wait for results of an hCG test done to check the health of your baby.
In most cases, there is no pain with collecting a urine sample.
There is very little chance of a problem from having a blood sample taken from a vein.
Collecting a urine sample does not cause problems.
The human chorionic gonadotropin (hCG) test is done to measure the amount of the hormone hCG in blood or urine to see if a woman is pregnant. HCG may also be measured to see if cancer of the ovaries or testicles is present.
These numbers are just a guide. The range for normal varies from lab to lab. Your lab may have a different range. Your lab report should show what range your lab uses for normal. Also, your doctor will evaluate your results based on your health and other factors. So a number that is outside the normal range here may still be normal for you.
Lessthan 5international units per liter (IU/L)
Pregnant women, 1 week of gestation (about 3 weeks afterthe last menstrual period):
Pregnant women, 2 weeks of gestation (about 4 weeks after theLMP):
Pregnant women, 3 weeks of gestation (about 5 weeks after theLMP):
Pregnant women, 4 weeks of gestation (about 6 weeks after theLMP):
Pregnant women, 6-8 weeks of gestation (about 8-10 weeks after theLMP):
Pregnant women, 12 weeks of gestation (about 14 weeks afterthe LMP):
Pregnant women, 13-16 weeks of gestation (about 15-18 weeks afterthe LMP):
Up to 200,000IU/L
You may not be able to have the test, or the results may not be helpful, if:
ByHealthwise StaffPrimary Medical Reviewer Sarah Marshall, MD Family Medicine E. Gregory Thompson, MD Internal Medicine Adam Husney, MD Family Medicine Specialist Medical Reviewer Siobhan M. Dolan, MD, MPH Reproductive Genetics Rebecca Sue Uranga, MD Obstetrics and Gynecology
Current as ofMarch 16, 2017
American College of Obstetricians and Gynecologists (2007, reaffirmed 2008). Screening for fetal chromosomal abnormalities. ACOG Practice Bulletin No. 77. Obstetrics and Gynecology, 109(1): 217-227.
Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
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Human Chorionic Gonadotropin (HCG) – Metro Health Hospital