Results
None of the 253 pregnancies with an sFlt-1/PlGF ratio of 38 or below developed early-onset pre-eclampsia. The prognostic prediction tool included sFlt-1 MoM, NT-proBNP and gestational age at time (GA) of repeated measurements. The area under the ROC curve (AUC) for early-onset pre-eclampsia diagnosis leading to delivery within one week was 88.247 (95% CI 0.822-0.934) for the prediction tool and 82.639 (95% CI 0.752-0.892) for the sFlt-1/PlGF + GA model (P=0.04). At an sFlt-1/PlGF ratio 655 cut-off the detection ratio was 31.9% (19.1-47.1) with false positive rate of 4.2% (1.7-8.5). With the same false positive rate, the detection rate with the prognostic prediction tool was 53.2% (38.1-67.9) (P=0.03).