Offering maternal serum screening with multiple markers (i.e., alpha-f
etoprotein, human chorionic gonadotropin, and unconjugated estriol) fo
r the detection of fetal neural tube defects, Down syndrome, and other
abnormalities, is now routine obstetrical practice. It is anticipated
that in the future, first-trimester screening and the addition of new
markers will be incorporated into screening programs.