Fig. 1

The schematic workflow of this study. The study involved 1,965 pregnancies consisting of 144 EOPE, 363 LOPE, 1458 healthy controls enrolled between 2019 and 2021 from six hospitals. The participants were divided into three cohorts. Cohort I, comprising 25 EOPE, 60 LOPE, 36 Preterm PE, 31 mild PE, 54 severe PE, and 289 healthy controls, was used to identify laboratory markers associated with different subtypes of PE and clinical characteristics. Cohort II, consisting of 29 EOPE, 65 LOPE, 39 Preterm PE, 31 mild PE, 63 severe PE and 285 healthy controls, was used to validate the results. Cohort III included 90 EOPE, 238 LOPE, 156 Preterm PE and 884 healthy participants and was further divided into a training dataset and an EV dataset. The training dataset was used to select optimal features for predicting PE and develop single and ensemble machine learning models. The EV dataset was used to validate and assess the performance of the established models