Study On The Changes And Clinical Application Of Coagulation And Fibrinolysis Related Indexes In Perinatal Women

Background and objectiveVenous thromboembolism(VTE)is a serious and potentially fatal disease.The basis of VTE exists in pregnant and postpartum women due to its special physiological changes,that is,blood hypercoagulability,venous stasis and vascular endothelial injury.Such changes make pregnant women at high risk for VTE.The incidence of VTE is five times higher among pregnant women than non-pregnant women of the same age.Meanwhile,The risk of VTE is five times higher in the postpartum period than during pregnany.After a cesarean section,the risk of developing postpartum VTE is increased four-fold compared to women who undergo vaginal delivery.Although absolute VTE rates in this population are low,obstetric-associated VTE is an important cause of maternal morbidity and mortality.With the continuous improvement of people’s living and education standards in China and the changes of fertility policy,female gestational age is delayed.The rate of advanced maternal age(≥35 years old)is higher than before.This changes are associated with an increased risk of VTE.The routinely use of low molecular weight heparin(LMWH)thromboprophylaxis in pregnant women post cesarean section is still controversial.The aim of this study is to analyze the changes of coagulation and fibrinolysis indexes in perinatal women combining routine coagulation assays,D-Dimer,thromboelastography and thrombotic markers and to analyze the influence of maternal age on coagulation and fibrinolysis indexes before delivery.We also explored the clinical significance of routinely use of LMWH after cesarean section and the correlation between various testing indexes and its clinical application value.MethodsA total of 88 healthy perinatal women who delivered in the obstetrics department,NanFang hospital of southern medical university from January 2019 to July 2019 were selected.The 88 pregnant women before delivery were divided into 4 groups according to age(≤24 years old,25-29 years old,30-34 years old,≥35 years old).Meanwhile,according to whether the pregnant women belonged to the elderly parturient,the pregnant women before delivery were divided into 66 cases of non-advanced maternal age group(age<35 years old)and 22 cases of advanced maternal age group(age≥ 35 years old).we expected to analyze the influence of maternal age on the indexes of coagulation and fibrinolysis.The 88 cases were divided into 44 cases of vaginal delivery group and 44 cases of cesarean section group according to different delivery methods.LMWH was not used in 44 parturients after vaginal delivery,whlie LMWH was routinely used after cesarean section in 44 parturients.Prenatal and postpartum peripheral blood of the two groups were collected for the following tests:blood routine test(HGB,HCT,PLT),routine coagulation assays(PT,APTT,TT,Fbg),D-Dimer,thromboelastography(R,K,Angle,MA,LY30,CI)and thrombotic markers(thrombomodulin,thrombin-antithrombin Ⅲcomplex,alpha2-plasmin inhibitor-plasmin complex,tissue plasminogen activator-inhibitor complex).Statistical analyses were performed using SPSS Version 20.0 software.Paired sample t test was used for intra-group comparison.The measurement data conforming to the normal distribution were expressed as mean±standard deviation.The independent sample t test was used for the comparison between the two groups,and the one-way anova was used for the comparison between the multiple groups.The measurement data that did not follow the normal distribution were represented by the median(quartile spacing).Statistical comparisons were tested with Mann-Whitney U test and Kruskal-Wallis H test.Spearman correlation analysis was used for correlation analyses between indexes.In all cases P<0.05 was considered statistically significant.Results1.The levels of TM in 88 pregnant women before delivery were significantly different between ≤24 years old group and≥ 35 years old group(adjusted P=0.034),while the difference between the other groups was not statistically significant(P>0.05);However,the differences of PT,APTT,TT,Fbg,D-Dimer,TAT,PIC,t-PAIC,HGB,HCT and PLT levels in different age groups were not statistically significant(P>0.05).Compared with the 66 cases of non-advanced maternal age group before delivery,the levels of D-Dimer,TM and PIC in the 22 cases of advanced maternal age group increased(P=0.022,0.005,0.020)while the levels of PLT decreased(P=0.035),with statistically significant differences;on the contrary,there was no significant difference in PT,APTT,TT,Fbg,TAT,t-PAIC,HGB and HCT levels(P>0.05).2.Compared with the vaginal delivery group before delivery,PIC level increased(P=0.035)and TM,TAT,t-PAIC and HGB levels decreased(P=0.000,0.006,0.000,0.000)in the vaginal delivery group after delivery,which differences were significant;however,there was no significant difference in D-Dimer,HCT and PLT levels(P>0.05).3.Compared with the cesarean section group before delivery,the PIC level in the cesarean section group after delivery increased(P=0.004)and the levels of TM,t-PAIC,HGB and HCT decreased(P=0.000,0.000,0.000,0.037),with statistically significant differences;while the D-Dimer,TAT and PLT levels showed no statistically significant differences(P>0.05).Compared with the vaginal delivery group after delivery,the postpartum TM,R and MA levels in the cesarean section group all increased(P=0.011,0.008,0.003),with statistically significant differences;while the D-Dimer,TAT,PIC,t-PAIC,K,Angle,LY30,CI,HGB,HCT and PLT levels showed no statistically significant differences(P>0.05).4.There was a correlation between D-Dimer and PIC in 88 pregnant woman before delivery(rs=0.619,P<0.01);while there was no correlation between routine coagulation assays and thrombotic markers(P>0.05).The correlation between D-Dimer,thrombotic markers and TEG parameters was observed in 44 parturients after vaginal delivery(P>0.05).Conclusions1.The age of pregnant women has a greater influence on TM level.Compared with non-advanced maternal age group,the vascular endothelial injury in advanced maternal age group may be more serious and the activation of fibrinolytic system may be more obvious.2.The blood coagulation and fibrinolysis systems in vaginal delivery women are in a high level dynamic balance state.Antepartum blood hypercoagulability was more obvious than postpartum,and the postpartum activation of fibrinolysis system was more obvious than antepartum.Moreover,D-Dimer was not as sensitive as PIC in reflecting changes in fibrinolytic activity in pregnant women.Thrombotic markers can be used to monitor the changes in the activity of maternal coagulation and fibrinolysis system.3.Compared with the vaginal delivery group after delivery,the postpartum coagulation and fibrinolytic system activation levels of the cesarean section group treated with LMWH anticoagulation were similar to those of vaginal delivery.4.There was no correlation between the routine coagulation assays and thrombotic markers in pregnant women before delivery.Meanwhile,the correlation was not found between postpartum thrombotic markers and TEG parameters.Clinician shoud choose each testing index according to the different clinical manifestation or the disease diagnosis.