The triple test, also called triple screen, the Kettering test or the Bart’s test, is an investigation performed during pregnancy in the second trimester to classify a patient as either high-risk or low-risk for chromosomal abnormalities. The term “multiple-marker screening test” is sometimes used instead. More specific it’s a blood test that measures three things called alpha-fetoprotein, human chorionic gonadotropin and unconjugated estriol.