The potential value of pre-delivery hematologic index in patients with placental abruption and perinatal outcomes

Abstract

Objective This study aimed to clarify the risk factors, clinical features, diagnosis, and management of placental abruption(PA), as well as explore the relationship between the severity of placental abruption and maternal and fetal outcomes. Another purpose of the study was to evaluate changes in hematological biomarkers before delivery in PA and whether their use in predicting the severity of PA. Methods A total of 310 cases of placental abruption among 56,895 women who delivered at our tertiary maternity center between December 2015 and February 2021 were retrospectively analyzed. Patients were classified into four groups based on abruption severity of grade 0, I, II or III, then clinical variables and in hematological biomarkers before delivery were compared among the four groups. The clinic data and pre-delivery hematological biomarkers of placental abruption of different severities were analyzed. Results The incidence of placental abruption in our sample was 0.54%. Primary symptoms of placental abruption included abdominal pain (49.6%), vaginal bleeding (39%), bloody amniotic fluid (24%), abnormal fetal heart rate (16.4%), or no symptoms at all (4.5%). Grade III abruption was significantly more likely to occur than abruption of other grades in patients with preterm delivery, hypertensive disorders in pregnancy, and anemia (P < 0.05). As the severity of placental abruption increased, birth weight and Apgar scores at 1 and 5 min decreased significantly, while the risk of neonatal asphyxia increased significantly. Overall, 0.64% of fetuses had cerebral palsy and 0.96% died. Among mothers, the risk of blood transfusion or cesarean section increased with abruption severity. Pre-delivery hematologic index, the lymphocytes, hemoglobin and fibrinogen decreased significantly(P < 0.05), while the neutrophils, neutrophil to lymphocyte ratio(NLR), prothrombin time(PT) and D-dimer increased significantly with abruption severity(P < 0.05). The variation in the level of coagulation indicators was corresponded to the amount of blood loss during postpartum hemorrhage. Conclusions With increasing severity of placental abruption was associated with adverse maternal and neonatal outcomes. The pre-delivery hematologic index, especially NLR, PT and D-dimer were associated with disease severity, further research should focus on the changes in the hematologic index in PA is critical to reveal the underlying pathophysiologic mechanisms.