After the blood sample is drawn, it's sent to a laboratory where a technician tests the blood for genetic defects and other disorders. In most cases, the results are ready within a few weeks. Your doctor will explain the results to you and, if a problem is diagnosed, give you information about ending the pregnancy or how best to care for your baby after birth.
Update Date 6/11/2014
Updated by: Cynthia D. White, MD, Fellow American College of Obstetricians and Gynecologists, Group Health Cooperative, Bellevue, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.