Chapter 11 Abnormalities of Blood Coagulation

blood test. Between 11 weeks and 13 6/7 weeks. The nuchal translucency is a special sonogram measuring the amount of fluid below the skin in the fetal neck. This in combination with blood tests for PAPP-A and HCG has a detection rate for aneuploidy from an extra chromosome 21 (Down syndrome) or 18 (Edward syndrome) of 75% - 86%. ................
................