Objective: To systematically review the efficacy and safety of modified cervical cerclage in reducing lower uterine segment bleeding due to placenta previa. Methods: A computerized search was performed in Wanfang Data

CNKI

VIP

the Cochrane Library

PubMed

EMBase

and Web of Science to identify studies on the efficacy and safety of modified cervical cerclage in the treatment of lower uterine segment bleeding due to placenta previa published up to July 2019. RevMan 5.3 software was employed. The effect sizes of outcome measures were described as relative risk（RR） and mean difference（MD） with 95% confidence intervals（95% CI）. The Q test and I2 values were used to perform tests for heterogeneity. Results: A total of 25 studies with 1984 patients were included

including 976 patients in control group and 1008 patients in experimental group. The results of meta-analysis showed that compared with the control group

the experimental group had a significantly higher effective rate of hemostasis(RR =1.09

95% CI: 1.05-1.14

P < 0.000 01] and significantly less operation time（MD =-23.84

95% CI:-24.82 to-22.87

P < 0.000 01）

intraoperative blood loss（MD =-324.91

95% CI:-332.83 to-316.98

P < 0.000 01）

intraoperative blood transfusion（MD =-2.22

95% CI:-2.58 to-1.86

P < 0.00001）

postoperative bleeding（MD =-6.35

95% CI:-7.60 to-5.09

P < 0.00001）

and length of hospital stay（MD =-2.05

95% CI:-2.39 to-1.72

P < 0.00001）; there were no significant differences in puerperal infection rate（RR = 0.38

95% CI:0.09-1.63

P < 0.00001） and postoperative recovery between the two groups. A further analysis was conducted on the indicators with heterogeneity and publication bias among the studies. Conclusion: Modified cervical cerclage is more effective than traditional hemostasis in reducing lower uterine segment bleeding due to placenta previa

and is relatively safe. However

it still needs to be further verified by large-sample and high-quality randomized controlled trials.