Redefining probability of preeclampsia in high risk women using PlGF later in pregnancy

Objective : To determine the effectiveness and gestational age-specific cut-off of Placental growth factor ( PlGF) in the second half of pregnancy for the prediction of adverse materno-fetal outcome among high-risk women. Methods : This secondary analysis explored associations between placental growth factor (PlGF) among women at high risk of PE at 20-22, 28-30, and 34-36 weeks of gestation. Women were divided into two groups based on PlGF levels cut-off derived after applying area under the receiver operating curve. Results: Of the 287 high risk women, 116(40.4%) had preeclampsia (PE). The cut off of PlGF was 224pg/ml, 211pg/ml and 176 pg/ml at 20-22, 28-30 and 34-36 weeks respectively, nearly 30% of the high risk women had PlGF below cut-off. The sensitivity and specificity of PE prediction using PlGF at 20-22 weeks was 81.0% and 72.2% respectively. For PlGF done at 28-30 weeks, the sensitivity and specificity of PE prediction till 32 weeks were 91.7% and 78.5% respectively. For PlGF done at 34-36 weeks, the sensitivity and specificity of PE prediction till 37 weeks was 95.8% and 73.3%, respectively. The negative predictive value of the PlGF at any gestation was nearly 90% or above for PE prediction till delivery. The accuracy of the test was highest at 28-30 weeks and for prediction before 37 weeks. Conclusion: The PlGF is a good marker to be done at 28-30 weeks for prediction of PE especially early onset and its adverse outcome; it can also be done at 34-36 weeks for preterm PE prediction.