The AFP test results, along with other factors such as maternal age, gestational age, and sometimes additional blood tests, are used to calculate the individual risk of certain abnormalities. The results are typically presented as a screening result with a specific risk factor, such as "1 in 1000" or "1 in 100."
If the AFP test or the combined screening indicates a higher risk of a specific abnormality, further diagnostic tests, such as ultrasound, amniocentesis, or chorionic villus sampling (CVS), may be recommended for a more accurate diagnosis.