[Analysis of misssed diagnosis and misdiagnosis of 1 212 cases with placental abruption].

Objective: To investigate the risk factors and clinical manifestations of placental abruption, and to analyze the causes of missed diagnosis and misdiagnosis. Methods: A retrospective analysis was conducted in 135 584 women who delivered in Women's Hospital, School of Medicine, Zhejiang University from January 2005 to December 2015. The diagnosis of placental abruption was made in 1 212 cases. According to the consistency of prenatal and postnatal diagnosis, they were divided into 3 groups. (1) The diagnosis was consistent prenatally and postnatally in 715 cases(58.99%, 715/1 212) as the diagnosis group. (2) In 312 cases (25.74%, 312/1 212), the diagnosis was made after birth as the missed diagnosis group. (3) In 185 cases (15.26%, 185/1 212), the diagnosis was made prenatally but excluded after birth as the misdiagnosis group. The disease classification was made, and the risk factors, clinical manifestations, lab results, the time of termination and perinatal outcomes were recorded in the 3 groups. The reasons of missed diagnosis and misdiagnosis were analyzed. Results: (1) In the 1 212 cases, the diagnosis of placental abruption was confirmed in 1 027 cases, with the incidence of 0.76% (1 027/135 584). The rate of missed diagnosis was 30.38% (312/1 027), and the rate of misdiagnosis was 0.14% (185/134 557) . (2) There were significant differences in the degree of placental abruption among the 3 groups (P<0.05). (3)Significant differences were found among the 3 groups regarding the ratio of hypertensive disorders, trauma, induced labor and advanced maternal age (all P<0.05). (4) There were statistically significant differences among the 3 groups regarding the incidence of vaginal bleeding, persistent abdominal pain and uterine tenderness, bloody amniotic fluid, increased uterine tension and stillbirth (all P<0.05). (5) There was no significant difference in the rate of abnormal fetal heart rate mornitoring among the 3 groups (P=0.22). The differences were statistically significant among the 3 groups when regarding the incidence of abnormal ultrasound finding and abnormal blood coagulation (P<0.01), with the highest incidence of abnormal ultrasound in the diagnosis group (68.1%) and the highest incidence of abnormal coagulation in the misdiagnosis group (24.9%). (6)There was statistically significant difference among the 3 groups when comparing the ratio of termination of pregnancy within 24 hours (P=0.01). (7) There were statistically significant differences among the 3 groups when the ratios of postpartum hemorrhage, DIC, neonatal asphyxia and perinatal death were compared (all P<0.05). The highest incidence of postpartum hemorrhage was in the diagnosis group (17.9%) and the lowest was in the misdiagnosis group (5.4%). The highest incidence of DIC was in the diagnosis group (3.9%) and the lowest was in the misdiagnosis group (0). The highest incidence of neonatal asphyxia was in the diagnosis group (30.6%) and the lowest was in the misdiagnosis group (7.6%). And for perinatal death, the highest incidence was in the diagnosis group (12.6%), the lowest was in the misdiagnosis group (2.2%). Conclusions: Placental abruption could be misdiagnosed when depending on risk factors, such as trauma. And it could be missed diagnosis during the induction of labor. Uterine contraction, abnormal fetal heart rate mornitoring, abnormal ultrasound and abnormal coagulation function are important in the diagnosis of placental abruption.