Triple marker test is a screening test which is done around the end of the first trimester. It is commonly called as triple test, triple screening, multiple marker or AFP marker. Triple marker test helps to detect whether the unborn baby is suffering with Down syndrome or not. This is a very useful method to know genetic defects in the babies before their birth. This test records the levels of some markers present in blood, namely, AFP (alpha-fetoprotein), HCG (human chorionic gonadotropin) and estriol. This test can be done successfully in clinics, hospitals and in diagnostic centres and the results should be discussed with your gynaecologist.