This test is not mandatory. However it is required in some states, such as California and New York. The results are usually back with in a week. This would show up in mother's blood stream. Elevated levels of AFP may indicate such defects as spina bifida or anencephaly.
Low levels suggest Down syndrome or other chromosomal defects.
If your test results do not come back normal don't panic. AFP can not predict if your child has these disorders it predicts the chances of having the disorder. If AFP detects a problem additional testing is usually ordered. This test is commonly done in 28th week of the pregnancy. This form of diabetes develops during pregnancy and is usually controlled by diet and exercise, which if left untreated may cause problems for mother and baby.