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Definition of Alpha Fetoprotein (AFP)
A protein the liver produces. In pregnancy the amount of AFP in the woman’s blood circulation increases, reflecting the activity of the fetus’s liver as it develops and becomes functional. A blood test measures AFP in the woman’s blood circulation early in the second trimester, between 15 and 22 weeks of pregnancy.
AFP in Pregnancy
Elevated Alpha fetoprotein levels in pregnancy may indicate a multiple pregnancy, neural tube defects or defects in the structure of the abdominal wall that allow the organs of the gastrointestinal system to form outside the body. Chronic liver disease, such as hepatitis or cirrhosis, also elevates AFP.
Excessive alcohol consumption and cigarette smoking are common causes of falsely high measures. Low AFP levels may indicate a pregnancy that is not as advanced as the woman believes or suggest the chromosomal disorder down syndrome.
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