Human Chorionic Gonadotropin (HCG) in Serum or Plasma

What Is HCG Used For?

HCG is primarily used to confirm pregnancy, especially in early stages when other tests may not be reliable. It can also help monitor high-risk pregnancies or detect complications like miscarriage or ectopic pregnancies. Doctors may also use HCG to evaluate conditions such as gestational trophoblastic disease (a rare pregnancy complication).

How Is the HCG Test Performed?

A blood sample is taken from a vein in your arm. The sample is sent to a lab where it is analyzed using an immunoassay method to detect HCG levels. Sometimes, urine samples may be tested for HCG, but blood tests are more accurate for early pregnancy detection.

When Might You Need an HCG Test?

You may need an HCG test if you suspect you are pregnant, especially if you missed a period or have other pregnancy symptoms. Doctors may also order it during pregnancy monitoring, after a miscarriage or ectopic pregnancy diagnosis, or in cases of suspected gestational trophoblastic disease.

What Do HCG Results Mean?

HCG levels rise steadily during early pregnancy, typically doubling every 48–72 hours. If you are pregnant, your HCG levels should increase over time. Abnormally low or rapidly declining levels may signal complications. Your doctor will interpret results in the context of your medical history and symptoms.