RT @NEJM: Cell-free DNA blood test for Down's in routine pregnancies has higher sensitivity/specificity than standard screen. http://t.co/Ml9lJK9qUI

RT @NEJM: Cell-free DNA blood test for Down's in routine pregnancies has higher sensitivity/specificity than standard screen. http://t.co/Ml9lJK9qUI (via Twitter http://ift.tt/1EGXMMl)