Obstetrics - Alpha-feto protein (AFP)
or MSAFP/Quad screen
An AFP (alpha-fetoprotien) test is a simple blood test. It can show whether your fetus has signs of some birth defects. This test is done between weeks 16 and 20 of pregnancy.
An AFP test is only a screening test. The most it can do is point to a possible problem. If your test returns with a positive result, other tests will be needed to confirm the results. Most AFP test results are normal.