Human Chorionic Gonadotropin, Beta (β-hCG)
Beta human chorionic gonadotropin (β-hCG) is a hormone produced mainly during pregnancy, largely by the developing placenta. Blood tests can detect and quantify it.
Doubles approximately every 48h in early viable pregnancy. >5 mIU/mL positive; <1 mIU/mL negative. Used for pregnancy confirmation, ectopic risk, trophoblastic disease monitoring, and germ cell tumor marker.
β-hCG rises early in pregnancy, so measuring it helps confirm pregnancy and, when repeated over time, gives clues about how a pregnancy is progressing. Levels typically climb rapidly in the first weeks. Outside of pregnancy, hCG can occasionally be produced by certain other conditions, which is why context matters.
A high or rapidly rising β-hCG is most often related to pregnancy, including possibilities such as more advanced dating or multiples. Less commonly, elevated hCG can be linked to other medical conditions, so unexpected results are interpreted in clinical context.
A low or slowly rising β-hCG may reflect very early pregnancy or a pregnancy that is not progressing as expected, and usually prompts repeat testing and evaluation.
There is no single 'normal' number; expected β-hCG values depend heavily on how far along a pregnancy is, and trends over time often matter more than one reading. Your clinician will interpret your result with your dates and any symptoms.
Sources
Educational context only, not medical advice or a diagnosis. Reference ranges vary by lab, age and sex; always discuss your results with a clinician.