Reasons, Preparation & Procedure to Conduct Alpha Fetoprotein Serum Test

Submitted on March 27, 2012

Alpha fetoprotein ranks among the main plasma proteins and is produced by the liver and the yolk sac in a fetus. The alpha fetoprotein levels are barely traceable in adults. In pregnant women, the maternal blood is drawn for investigating the status of the fetus. When examined, the alpha fetoprotein serum levels in the blood can indicate if the baby is normal. If the levels are unusually low or high, there could be possible birth defects related to chromosomal abnormalities, neural tube disorders or omphalocoele.

Reason for Alpha Fetoprotein Serum

 The serum alpha fetoprotein test may be done as a normal routine investigation to determine the health of the fetus, especially if the prospective parents have a family history of certain abnormalities or if the prior baby was born with congenital defects. However, it may also be done specifically if the gynecologist has doubts regarding the fetus in connection to its size, condition and development that may be indicated during a routine checkup or an ultrasound. If the serum alpha-fetoprotein levels are high, it could be indicative of abdominal wall defects and neural tube defects. On the other hand, if the levels are very low, there could be a possibility of chromosomal defects like Down’s syndrome in the fetus. Doing this test helps in preparing the parents to deal with their baby’s condition (if any) and also assists in ascertaining the further course of action.


This test is usually conducted in the 16th week of pregnancy as it is at this time that the levels can indicate a possible defect. Hence, before going for the test, it is essential to make sure the date of the last period so as to correctly judge the age of the fetus. Clearing your doubts by talking to your gynecologist beforehand will also prove beneficial in keeping you calm, relaxed and mentally prepared.


Before blood is drawn from the inner portion of the elbow joint with a needle and syringe, the technician will prepare the area by rubbing it down with an antiseptic solution or spirit. An elastic band may be tied just above the area so as to facilitate the collection of blood from the desired vein. The fist is to be clenched before the blood is drawn so as to allow it to flow out smoothly into the syringe. After the needed amount of blood is collected, the elastic band is released and pressure if applied on the puncture wound. The blood is then processed and the results may come after approximately a week.