Alpha-fetoprotein: A protein manufactured by the fetal yolk sac, and later by the fetus' gastro-intestinal tract and liver. A test for levels of AFP in the mothers blood can help detect Down's syndrome, spina bifida, and other abnormalities.
Estriol: Estriol (also oestriol) is one of the three main estrogens produced by the human body. It is also a steroid hormone produced mostly during pregnancy (mostly late pregnancy,)
Human chronic gonadotropin (HCG): A hormone that is produced by the placenta within several days of conception to help maintain the corpus luteum during the early weeks of pregnancy. The presence of this hormone in the woman’s urine and
blood is an indication of pregnancy.
inhibin A: A protein hormone secreted by the corpus luteum and the placenta, present in maternal serum during pregnancy.
