Low Molecular Weight Heparin For Preventing Preeclampsia And Its Effect On Pregnancy Outcome:A Meta-analysis

Objective:Low-molecular-weight heparin was used in women with high risk of preeclampsia(PE)from early pregnancy to investigate the effect of low molecular weight heparin on preventing preeclampsia and its effect on pregnancy outcome.Method:Systematic review and meta-analysis of relevant research conducted according to the inclusion and exclusion criteria was performed using search of medical databases Pubed,Web of Science,Cochrane Library and CNKI,WanFang database,WeiPu database.we selected the literature that met our inclusion and exclusion criteria by two reviewers,and then the quality evaluation of literature was performed and the relevant data was extracted.Review Manager 5.3 software was used to make meta-analyze about the literatures which met the inclusion criteria.The indicators mainly included the incidence of pre-eclampsia,the incidence of fetal growth restriction(FGR),the gestational age at delivery,the incidence of postpartum hemorrhage,and the incidence of placental abruption.Results:Nine studies which including 1,089 patients met the inclusion criteria and were divided into two subgroups for meta-analysis depending on the dosing regimen.The results showed that:(1)The incidence of preeclampsia(RR=0.37,95%CI:0.24-0.58,P<0.0001)and the incidence of fetal growth restriction(RR=0.24,95%CI:0.12-0.49,P<0.0001)in the LMWH group were lower than those in the non-anticoagulant group,and the difference was statistically significant.Compared with the non-anticoagulant group,LMWH group could prolong the gestational age at delivery(SMD=1.02,95%CI:0.28~1.75,P=0.007).(2)The incidence of preeclampsia in the LMWH+ LDA group was lower than that in the LDA group and the difference was statistically significant(R = 0.67,95% CI: 0.50-0.91,P = 0.01),but the sensitivity was poor and further research was needed.The incidence of fetal growth restriction was lower in the LMWH+LDA group than in the LDA group and the difference was statistically significant(RR=0.71,95% CI: 0.55-0.93,P=0.01).There was no significant difference between the LMWH+ LDA group and the LDA group in prolonging the gestational age at delivery(SMD=0.12,95%CI:-0.11-0.36,P=0.30).Compared with the LDA group,the incidence of placental abruption(RR=0.79,95%CI:0.31-2.04,P=0.63)and the incidence of postpartum hemorrhage(RR=1.09,95%CI:0.49-2.42,P=0.83)did not increase in LMWH+LDA group.The difference was not statistically significant.Conclusion:LMWH plays an important role in preventing the occurrence of preeclampsia in high-risk pregnant women and improving pregnancy outcomes.This result provides evidence-based medical evidence for the prevention of preeclampsia in LMWH.