Current CHS and NHBPEP criteria for severe preeclampsia do not uniformly predict adverse maternal or perinatal outcomes

Objective: To determine the association between adverse maternal/perinatal outcomes and Canadian and U.S. preeclampsia severity criteria. Methods: Using PIERS data ((P) under bar reeclampsia (I) under bar ntegrated (E) under bar stimate of (R) under bari (S) under bark), an international continuous qualityimprovement project for women hospitalized with preeclampsia, we examined the association between preeclampsia severity criteria and adverse maternal and perinatal outcomes (univariable analysis, Fisher's exact test). Not evaluated were variables performed in < 80% of pregnancies (e.g., 24-hour proteinuria). Results: Few of the evaluated variables were associated with adverse maternal (chest pain/dyspnea, thrombocytopenia, 'elevated liver enzymes', HELLP syndrome, and creatinine > 110 mu M) or perinatal outcomes (dBP > 110 mm Hg and suspected abruption) (at p < 0.01). Conclusions: In the PIERS cohort, most factors used in the Canadian or American classifications of severe preeclampsia do not predict adverse maternal and/or perinatal outcomes. Future classification systems should take this into account.