Identification Of The High Risk Factors Of Placental Abruption And Discussion On The Perinatal Outcomes

Background:Placental abruption is one of the severe complications during gestation period which is defined as complete or partial placenta in normal position separating from the uterine wall after 20 gestational age or during delivery. The primary pathogenesis of placental abruption is unclear at present, however, it increase the perinatal morbidity and mortality of the mother and the fetus. Risks of cardiovascular morbidity and mortality are 3 to 4 times higher in female with placental abruption than in normal female, and the morbidity of placental abruption is 0.46% to 2.1% in China. The severe placental abruption can be clearly diagnosed in clinic, however, the symptoms and signs of early-and medium-stage placental abruption dose、not significantly different, and there have been no assay indices or other diagnostic methods for early diagnosis. Besides, ultrasonography is limited. The prognosis of placental abruption is associated with early diagnosis and timely treatment. The high risk factors of placental abruption are as follows:multipara, advanced maternal age, preeclampsia, chronic hypertension, as well as past medical history which includes history of placental abruption, cesarean section, stillbirth, chorioamnionitis, premature rupture of fetal membranes, multiple gestation, small for gestational age, trauma, anemia, smoking and alcoholism. How to identify placental abruption at the early stage and treat timely in different individuals is the focus of perinatal field. The article probed the risk factors, early identification, diagnosis and treatment of placental abruption, and assessed the prognosis for pregnant and lying-in women as well as the fetuses, with an aim to offer help in clinic.Methods:210 cases of placental abruption in the affiliated maternity hospital of Zhejiang University School of Medicine from January,2014 to January,2015 were retrospectively collected and divided into the mild placental abruption group and severe placental abruption group based on the size of the blood clot embedded on the surface of the placenta, area of placental separation, as well as with/without combined shock, fetal distress or stillbirth in accordance with the diagnostic criteria of The Obstetrics and Gynecology by Cao Zeyi. The general information, initial symptoms, postpartum hemorrhage, and clinical outcomes of the perinatal infants of the pregnant women in the two groups were compared. Rank sum test and chi-square test were utilized in analyzing the measurement data and enumeration data, respectively.Results:1. Comparison of the general information in the two groups:the average age and average gestational weeks of the mild placental abruption group were 30.1±4.2 and 35.6±4.2 years old, respectively. Those of the severe placental abruption group were 28.8±4.0 and 33.4±6.0 gestation age, respectively. There were no significant differences of the age and gestation weeks of the two groups (P>0.05). There was no statistical significance when comparing the age, parity and gestational age (P>0.05)2. Comparison of the pregnancy complications in the two groups:the occurrence of hypertensive disorder complicating pregnancy in the mild and severe placental abruption were 5.6% and 59.2%, respectively, with significant difference (p<0.0001); while the gestational diabetes, scarred uterus, twin pregnancy and rate of premature rupture of fetal membranes in the two groups were of no significant differences (P>0.05)3. Identification of the initial symptoms of placental abruption:the initial symptoms in the 210 cases covered:vaginal bleeding (66,31.4%), persistent abdominal pain (45, 21.5%), and abnormal fetal heart rate (67,31.9%), and typical triad (abdominal pain, vaginal bleeding, and abnormal fetal heart rate) only existed in 14 cases (6.7%). The placental abruption of less than 34 gestational weeks mainly manifested as vaginal bleeding (49%), that of greater than 34 gestational weeks and less than 37 gestational weeks principally manifested as vaginal bleeding (29%) and abnormal fetal heart rate (25%), while that of greater than 37 gestational weeks mostly manifested as abnormal fetal heart rate (33%)4. Comparison of the initial symptoms in the two groups:the initial symptoms of placental abruption in the mild and severe placental abruption groups were dominated by vaginal bleeding and typical triad, and those confirmed with B ultrasound and to emerge coagulopathy were 24.2% vs 55.1%; 1.9% vs 22.4%; 14.9% vs 49.0%; 3.7% vs 18.4%, respectively. There were statistical differences between the two groups (p<0.0001). However, the occurrence of persistent abdominal pain or abnormal fetal heart rate as the initial symptom was of no significant difference (p>0.05)5. Analysis of the perinatal outcomes in the two groups:the occurence of coagulopathy and the mortality of perinatal fetuses were remarkably higher in the severe placental abruption group than in the mild placental abruption group, which were 26.5% vs 6.2%; 18.4%vs 3.7%, respectively, with significant differences (p<0.0001). The 1-minute Apgar score,5-minute Apgar score, as well as weight of the neonatal in the mild and severe placental abruption groups were 10 (1.0) vs 10(8.0)、10(0.0) vs 10(4.0)、2850.00(1450.00)g vs 2230±1058g, respectively, with significant differences (P<0.05). The volume of postpartum bleeding in the mild group were 200 (100) ml, and severe group were 300 (200) ml, with significant difference (p<0.001)6. Risk factors of severe placental abruption:Multi-factor logistic regression analysis indicated that hypertensive disorder complicating pregnancy, abnormal vaginal bleeding, typical triad of placental abruption (abdominal pain, vaginal bleeding, and abnormal fetal heart rate), as well as coagulopathy were distinctly related to severe placental abruption (p<0.0001), with the OR of 21.62、3.16、8.28 and 6.66.Conclusions:Firstly, placental abruption with various orders of severity could occur in any gestational week and parity of pregnant women of normal reproductive age.Secondly, hypertensive disorder complicating pregnancy, vaginal bleeding, typical triad of placental abruption, and coagulopathy were important high risk factors that affected the severity of placental abruption.The clinical manifestation of placental abruption was of no specificity, with the early preterm birth group, preterm birth group, and full-term birth group being dominated by vaginal bleeding, vaginal bleeding and abdominal pain, and fetal heart rate changes, respectively. Early diagnosis of severe placental abruption, together with prediction of the perinatal outcomes could be improved through combining the gestational weeks with the initial clinical manifestation.