A 14 weeks pregnant female is found to have increased nuchal thickness on an ultrasound scan. In Down's syndrome, 2nd trimester quadruple test includes all, EXCEPT:

Quadruple or "quad" test for diagnosing Down's syndrome: AFP Human chorionic gonadotropin (hCG) Unconjugated estriol Dimeric inhibin alpha At 15 to 20 weeks, Down syndrome pregnancies are characterized by, AFP value of approximately 0.7 MoM Human chorionic gonadotropin (hCG) level of approximately 2.0 MoM Unconjugated estriol concentration of approximately 0.8 MoM Dimeric inhibin alpha is about 1.8 MoM First three measurements are known as 'triple test', also used to screen for trisomy 18, in which all three serum markers are decreased. Ref: Cunningham F.G., Leveno K.J., Bloom S.L., Hauth J.C., Rouse D.J., Spong C.Y. (2010). Chapter 13. Prenatal Diagnosis and Fetal Therapy. In F.G. Cunningham, K.J. Leveno, S.L. Bloom, J.C. Hauth, D.J. Rouse, C.Y. Spong (Eds), Williams Obstetrics, 23e.