Preeclampsia is a leading cause of pregnancy related maternal death. The earlier the gestational age at diagnosis, the higher the risk of maternal death exists. The risk of maternal death is 4 times higher if preeclampsia develops around 32 weeks gestation than after this gestational age. Thus, the identification of patients at risk for severe and/or early onset preeclampsia followed by prophylactic interventions may prevent or delay the clinical presentation of the disease and/or reduce its severity.Abnormal uterine artery Doppler velocimetry (UADV) as well as abnormal maternal plasma concentrations of proangiogenic and antiangiogenic factors are risk factors for the subsequent development of preeclampsia.Plasma concentrations of PIGF and sVEGFR-1 were measured in 77 pregnant women at risk to develop preeclampsia. Plasma samples were obtained at the time of ultrasound examination between 22 and 26 weeks of gestation.Abnormal UADV, maternal plasma PIGF of <317 pg/ml and sVEGFR-1> 3300 pg/ml were independent risk factors for the occurrence of preeclampsia, severe preeclampsia, early onset preeclampsia, and IUGR.Serum PIGF is significantly lower in preeclamptic patients.Serum SVEGFR-1 is significantly higher in preeclamptic patients.Low serum PIGF and high serum SVEGFR-1 are significantly correlated to poor perinatal outcome (pre term labor, IUGR).The combination of abnormal UADV and maternal plasma PIGF concentration of <317 pg/ml and sVEGFR-1>3300 pg/ml in the second trimester is associated with a high risk for preeclampsia and early onset and/or severe preeclampsia.