Why is a Quad test done during pregnancy?

Q: My wife is 2 years old and is in her 15th week of pregnancy. She conceived with the help of Clomiphene and HCG injections and took progesterone for three months. After her 12th week, she was advised to go for PAPP-A test along with beta HCG test. The results are as follows: beta HCG –37945.5 IU/L (Normal range given 18300 – 137000); PAPP-A 2.26 micro g/ml (Normal range at 13 weeks 4.04 to 46.00 micro g/ml). The doctor says that we will have confirmed results only after a Quad test, for which blood sample is taken and results are expected after three weeks. As the PAPP-A results shows less, we are worried about the baby’s growth. What does this result mean and what implications will it have?

A:Quad test is the test, which is a screening test to diagnose the possibility of Down's syndrome and abnormal 18 chromosome; it is also done to check for any fault with the nervous system of the baby. It takes only 24-48 hours to get the result. Every woman above the age of 35 years is advised to undergo this test. In case any possibility of such defect in the baby, then technique of amino system is advised.