Objective. To evaluate the ability of endoglin, placental growth factor (PlGF) and the soluble form of vascular endothelial growth factor receptor (sFlt-1) measurements in gestational weeks 24–28 were used to predict pre-eclampsia. Design. Observational, prospective study. Setting. Department of Gynecological, Obstetrical Sciences and Reproductive Medicine, University of Messina. Sample. Fifty-two pre-eclamptic and 52 healthy pregnant women. Methods. A maternal serum sample was frozen and stored at 1-h 50-g glucose challenge test between 24 and 28 weeks’ gestation. A second maternal serum sample was collected at admission for the onset of the disease in the pre-eclamptic group and at admission for delivery in the control group. Levels of endoglin, sFlt-1 and the PlGF were measured in the stored serum. Pre-eclamptic subjects were also divided into women with early-onset (<37 weeks) and women with late-onset pre-eclampsia (≥37 weeks). Results. Levels of endoglin, sFlt-1, and sFlt-1: PlGF ratio were found to be higher in the pre-eclamptic group in both trimesters. No differences were found between early- and late-onset pre-eclamptic. The Receiver Operating Characteristics curve, applied to the second trimester marker values, showed the best diagnostic profile for sFlt-1: PlGF (area under the curve, AUC =0.92) followed by endoglin (AUC =0.88), sFlt-1 (AUC =0.87) and PlGF (AUC = 0.83). This finding was confirmed by Bayesian analysis which highlighted a specificity, a sensitivity, a diagnostic accuracy, a positive predictive value and a negative predictive value of 88.5% for sFlt-1: PlGF using a cut-off of 38.47. Conclusions. Endoglin, PlGF and sFlt-1 might be used as markers for predicting pre-eclampsia, but sFlt-1: PlGF seems to be more accurate.