First‐trimester maternal serum pregnancy‐associated plasma protein‐A and pre‐eclampsia

Abstract

Objectives: To examine the relationship between low maternal serum pregnancy‐associated plasma protein‐A (PAPP‐A) and uterine artery pulsatility index (UtA‐PI) at 11 + 0 to 13 + 6 weeks with subsequent development of pre‐eclampsia (PE). Methods: UtA‐PI and serum PAPP‐A were measured in women attending for routine care at 11 + 0 to 13 + 6 weeks of gestation. In the population, 156 (1.9%) women developed PE, including 32 (0.4%) in whom delivery was before 34 weeks (early PE) and 124 (1.5%) with delivery at 34 weeks or more (late PE); 7895 (98.1%) women had no PE. Regression analysis was used to examine which of the factors amongst maternal characteristics, log PAPP‐A multiples of the median (MoM) and log UtA‐PI MoM contributed to the prediction of PE. Results: The median PAPP‐A MoM was 1.002 (interquartile range (IQR), 0.685–1.411) in the unaffected group, 0.555 (IQR, 0.463–0.922) in early PE and 0.911 (IQR, 0.580–1.247) in late PE. Serum PAPP‐A was below the 5th centile in 21.9% of early PE and 6.5% of late PE cases. The PAPP‐A‐related patient‐specific risk for PE was strongly influenced by maternal characteristics. There was a significant association between log UtA‐PI MoM and log PAPP‐A MoM (P = 0.001), and the detection rate of screening for PE by maternal variables and UtA‐PI was not improved by inclusion of PAPP‐A. Regression analysis was used to establish tables that allow modification of the maternal history and PAPP‐A‐related patient‐specific risk for PE by the measurement of UtA‐PI. Conclusions: Low PAPP‐A is a marker for subsequent development of PE. The PAPP‐A‐related patient‐specific risk for PE can be modified by the measurement of UtA‐PI. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.