A Meta-analysis Of Pregnancy Outcomes On Aspirin And Low Molecular Weight Heparin In Patients Who Are Recurrent Pregnancy Loss With Pre-thrombotic State

Objective:The study aims to focus on patients who are recurrent pregnancy loss with pre-thrombotic state,by Meta analysis and system evaluation on the use of ASA alone and a combination of LMWH on pregnancy outcomes in patients who are recurrent pregnancy loss with pre-thrombotic status,aims to explore what kind of anticoagulant therapy for patients who are recurrent pregnancy loss with pre-thrombotic state to get more clinical advantages,Thus provide effective basis for improving the pregnancy outcome of the patients.Methods:Related literatures were searched in Chinese databases:CNKI,Wan fang database and English databases:Pub Med,The Cochrane Library,Web of Science,etc.The retrieval time was from the establishment of the database to August 1,2021.Strictly follow the inclusion and exclusion criteria,strictly screen the literature,and include the literature that meets the requirements.The main indicators observed were:Live-birth rate,Preterm birth rates,Abortion rate,Changes in hormone levels,and Changes in Coagulation indicators Adverse reactions and complications.Data were extracted,the quality of the study was evaluated,and Meta analysis was conducted on the extracted relevant data and data by using Stata 16.0 software.Results:A total of 12 Chinese literatures and 4 English literatures were included in this study,with a total sample size of 1522,including762 in experimental group and 760 in control group.In terms of pregnancy outcome,the combination therapy significantly increased the live birth rate of RPL patients with PTS compared with the control group（LDA alone）[RR=1.296,95%CI（1.220,1.376）,P=0.000].Decreased abortion rate[RR=0.391,95%CI（0.307,0.498）,P=0.000];Reduced preterm birth rate[RR=RR=0.562,95%CI（0.344,0.921）,P=0.022].In terms of changes in hormone levels,the combination therapy significantly increased the effect ofβ-HCG levels in RPL patients with PTS compared to the control group（LDA alone）[SMD=13.822,95%CI（8.666,18.978）,P=0.000].The effect of E₂ level was increased[SMD=2.733,95%CI（0.937,4.529）,P=0.003]and the change of P level[SMD=2.751,95%CI（1.614,3.887）,P=0.000],and the success rate of fetal preservation was improved.In terms of coagulation function indexes,D-D level in the experimental group（combined drug group）decreased more significantly than that in the control group[SMD=-2.566,95%CI（-3.019,-2.114）,P=0.000].The change of TT level was increased[SMD=1.493,95%CI（1.311,1.675）,P=0.000];The fibrinogen level（FIB）decreased significantly[SMD=-2.363,95%CI（-3.156,-1.570）,P=0.000].Tissue plasminogen activator（T-PA）level was increased[SMD=1.801,95%CI（0.140,3.461）,P=0.034].Plasminogen activator inhibitor（PAI-1）decreased significantly[SMD=-1.527,95%CI（-2.738,-0.316）,P=0.013],thus improving the success rate of fetal preservation.Complications and adverse reactions were reduced[RR=0.569,95%CI（0.442,0.733）,P=0.000],thus improving the safety of clinical application.Conclusions:Low-dose aspirin combined with low molecular weight heparin could improve the pregnancy outcome of patients who are RPL with PTS and the patients’hyper coagulable state,which was better than use LDA alone in efficacy,and the safety of clinical application was much higher,but clinical trials of more samples are needed to further verify it.