Human Chorionic Gonadotropin (hCG)

This is a test to confirm and monitor pregnancy or to diagnose trophoblastic disease or germ cell tumors.

As early as 10 days after a missed menstrual period (some methods can detect hCG even earlier, at one week after conception) or if your caregiver thinks that your symptoms suggest ectopic pregnancy, a failing pregnancy, trophoblastic disease, or germ cell tumors. hCG is a protein produced in the placenta of a pregnant woman. A pregnancy test is a specific blood or urine test that can detect hCG and confirm pregnancy. This hormone is able to be detected 10 days after a missed menstrual period, the time period when the fertilized egg is implanted in the woman's uterus. With some methods, hCG can be detected even earlier, at one week after conception.

During the early weeks of pregnancy, hCG is important in maintaining function of the corpus luteum (the mass of cells that forms from a mature egg). Production of hCG increases steadily during the first trimester (8-10 weeks), peaking around the 10th week after the last menstrual cycle. Levels then fall slowly during the remainder of the pregnancy. hCG is no longer detectable within a few weeks after delivery. hCG is also produced by some germ cell tumors and increased levels are seen in trophoblastic disease.

SAMPLE COLLECTION

hCG is commonly detected in urine. The preferred specimen is a random urine sample collected first thing in the morning. hCG can also be measured in blood drawn from a vein in the arm.

NORMAL FINDINGS

Qualitative: negative in non-pregnant women; positive in pregnancy

Quantitative:

  • Gestation less than 1 week: 5-50 Whole HCG (milli-international units/mL)

  • Gestation of 2 weeks: 50-500 Whole HCG (milli-international units/mL)

  • Gestation of 3 weeks: 100-10,000 Whole HCG (milli-international units/mL)

  • Gestation of 4 weeks: 1,000-30,000 Whole HCG (milli-international units/mL)

  • Gestation of 5 weeks 3,500-115,000 Whole HCG (milli-international units/mL)

  • Gestation of 6-8 weeks: 12,000-270,000 Whole HCG (milli-international units/mL)

  • Gestation of 12 weeks: 15,000-220,000 Whole HCG (milli-international units/mL)

  • Males and non-pregnant females: less than 5 Whole HCG (milli-international units/mL)

Beta subunit: depends on the method and test used

Ranges for normal findings may vary among different laboratories and hospitals. You should always check with your doctor after having lab work or other tests done to discuss the meaning of your test results and whether your values are considered within normal limits.

MEANING OF TEST

Your caregiver will go over the test results with you and discuss the importance and meaning of your results, as well as treatment options and the need for additional tests if necessary.

OBTAINING THE TEST RESULTS

It is your responsibility to obtain your test results. Ask the lab or department performing the test when and how you will get your results.