Prediction of stillbirth from placental growth factor at 11-13 weeks

Objectives: To investigate whether measurement of maternal serum placental growth factor (PLGF) at 11-13 weeks’ gestation improves the performance of screening for stillbirths that is achieved by a combination of maternal factors and first trimester biomarkers such as maternal serum pregnancy associated plasma protein-A (PAPP-A), ductus venosus pulsatility index for veins (DV-PIV) and uterine artery pulsatility index (UT-PI) PI and to evaluate the performance of screening of this model for all stillbirths and those due to impaired placentation and unexplained causes.<br /><br />Methods: This was a prospective screening study of 45,452 singleton pregnancies including 45,225 live births and 227 (0.49%) antepartum stillbirths; 131 (58%) were secondary to impaired placentation and 96 (42%) were due to other or unexplained causes. Multivariate logistic regression analysis was used to determine whether the addition of maternal serum PLGF improved the performance of screening that was achieved by a combination of maternal factors and PAPP-A, DV-PIV and UT-PI.<br /><br />Results: Significant contribution to the prediction of stillbirths was provided by maternal factor derived a priori risk and MoM values of PLGF, DV-PIV and UT-PI but not serum PAPP-A. A model combining these variables predicted 42% of all stillbirths and 61% of those due to impaired placentation, at false positive rate of 10%; within the impaired placentation group the detection rate of stillbirth at <32 weeks’ gestation was higher than that of stillbirth at >37 weeks (71% vs 46%; p=0.031).<br /><br />Conclusions: The results of our study demonstrate that a high proportion of stillbirths due to impaired placentation can be effectively identified in the first trimester of pregnancy. The extent to which such stillbirths could be prevented remains to be determined.