Pregnancy-Associated Plasma Protein-A (PAPP-A):- Pregnancy-associated plasma protein A (PAPP-A) is a key regulator of insulin-like growth factor bioavailability essential for normal fetal development. In maternal blood, this protein increases with gestational age and then rapidly decreases after delivery. Free Beta-Human Chorionic Gonadotropin (B-hCG):-Human chorionic gonadotropin (hCG) is a chemical created by trophoblast tissue, tissue typically found in early embryos and which will eventually be part of the placenta. Measuring hCG levels can be helpful in identifying a normal pregnancy, pathologic pregnancy, and can also be useful following an aborted pregnancy.