To analyze the relationship between placental abruption severity and maternal pregnancy outcome and to explore the predictive value of pre-delivery laboratory test results for the severity of placental abruption. The clinical datas of 126 patients with placental abruption diagnosed and treated in our hospital over the past 4 years were retrospectively analyzed. The severity of placental abruption was divided into degrees I to III. The pre-delivery laboratory results of all patients and data on maternal and fetal delivery outcomes were collected. The analysis of maternal outcomes showed that the volumes of antepartum, intrapartum and postpartum hemorrhage and the rates of utero-placental apoplexy, uterine compression sutures and vascular embolization significantly increased with increasing placental abruption severity. Fetal delivery data revealed that 1- and 5-min Apgar scores decreased significantly with increasing placental abruption severity. Pre-delivery laboratory findings suggest that the white blood cell count, hemoglobin, hematocrit, platelet count, albumin, aspartate aminotransferase (AST), creatinine, prothrombin time (PT), prothrombin activity, prothrombin time - international standardization ratio (INR), D-dimer, fibrinogen (FIB), and fibrin degradation products (FDP) changed significantly with increasing placental abruption severity. Further analysis by Spearman and Pearson correlation found that the pre-delivery volume of antepartum hemorrhage, D-dimer, FDP and other indicators were correlated with placental abruption severity. The harm of placental abruption to pregnant women and neonates increases with increasing abruption severity. Some laboratory test results can be predictors of placental abruption degree. •Predictive value of pre-delivery laboratory test results.•Placental abruption severity prediction.•Correlation of placental abruption severity and pregnancy outcome.