Alterations in Placental Growth Factor Levels before and after the Onset of Preeclampsia Are More Pronounced in Women with Early Onset Severe Preeclampsia

It has been established that the serum placental growth factor (PlGF) decreases and the soluble fms-like tyrosine kinase-1 (sFlt-1) increases in women with preeclampsia. However, there have been no studies on the relation between preeclampsia onset time and the changes in PlGF and sFlt-1. Furthermore, the PlGF and sFlt-1 levels have not been evaluated using their reference values specific to each gestational age. In this study we reevaluated the serum PlGF and sFlt-1 levels before and after the clinical manifestation of early and late onset severe preeclampsia using the new reference values developed in our recent longitudinal study. Blood specimens were obtained immediately after the clinical manifestation of severe preeclampsia in 34 referred women, and both before and after the clinical manifestation in 8 women receiving a routine checkup at our institute. Both women with early and those with late preeclampsia showed decreased PlGF and increased sFlt-1 levels compared to normotensive controls at 28 and 37 weeks (n=68). However, those with early onset preeclampsia had a higher incidence of low PlGF (<5th percentile on the reference values) and high sFlt-1 (>or=95th percentile) than those with late onset (low PlGF: 93% vs. 55%; high sFlt-1: 100% vs. 60%). log10PlGF (r=0.574, p<0.001) and log10(sFlt-1/PlGF) (r=-0.556, p<0.001) were correlated with the week of onset of preeclampsia. Before the onset of preeclampsia, the incidence rate of low PlGF in the women with early onset preeclampsia was 100% (5/5), whereas that in the women with late onset preeclampsia was 0% (0/2) (p=0.048). Therefore, alterations in the PlGF levels both before and after the onset of preeclampsia may be more pronounced in women with early onset than those with late onset severe preeclampsia.