Alpha-Fetoprotein (AFP)
Alpha-fetoprotein (AFP) is a protein made mainly by the liver, and it is normally high in babies before birth but low in most adults. The test measures how much AFP is in your blood.
In adults, AFP is used chiefly to help monitor certain known liver and reproductive-organ conditions, and during pregnancy it has a separate role in prenatal screening. It is generally not a stand-alone screening or diagnostic test outside of specific clinical situations. Trends over time are usually more meaningful than one value.
An elevated AFP is not a diagnosis and has several benign explanations. Pregnancy naturally raises AFP, and non-cancerous liver conditions such as hepatitis and cirrhosis, along with liver injury or regeneration, can also lift it. Your clinician interprets AFP in light of your age, pregnancy status, liver health, and other tests rather than reacting to a single number.
A low or normal AFP is the expected finding in most non-pregnant adults and is generally reassuring. It simply reflects a low level of this protein in the blood at the time of testing.
There is no universal target, since the meaningful range depends on whether you are pregnant, your liver health, and why the test was ordered. A clinician should interpret AFP in your specific context rather than against a generic cutoff.
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.