First-trimester maternal serum screening and the risk for fetal distress during labor.

Objective: The purpose of this study was to assess whether low pregnancy-associated plasma protein-A (PAPP-A) levels in the first trimester are related to the risk of emergency cesarean section delivery (CS) for fetal distress during labor and fetal intrapartum acidemia.

Study Design: We prospectively studied patients who requested first-trimester biochemical screening for Down syndrome.

Results: Among the 1037 women who were enrolled, 152 women (14.