Screening for adverse pregnancy outcome at early gestational age.

In the past two decades second-trimester maternal serum screening for Down syndrome has been the most common strategy for prenatal diagnosis of chromosomal aneuploidies. More recently, screening for and diagnosis of chromosomal abnormalities have increasingly been performed in the first trimester. With improvements and technological advances in ultrasound, it is now possible to identify many fetal anomalies at 11-13 weeks of gestation. During the same period biochemical markers in maternal serum (PAPP-A and hCGß) combined with sonographic measurement of nuchal translucency achieve a Down syndrome detection rate of 85% with a 5% false-positive rate. We describe here the potential of first-trimester markers to screen for Down syndrome as well as other adverse outcomes such as fetal loss, pre-eclampsia, intrauterine growth retardation, and preterm delivery. This early consultation may be the opportunity to help counsel patients and to screen for other adverse complications during pregnancy, such as pre-eclampsia, and to manage potential adverse pregnancy outcomes.