%0 Journal Article
%T Cervical priming before surgical abortion up to 13+6 weeks' gestation: a systematic review and metaanalyses for the National Institute for Health and Care Excellence-new clinical guidelines for England.
%A O'Shea LE
%A Lord J
%A Fletcher J
%A Hasler E
%A Cameron S
%J Am J Obstet Gynecol MFM
%V 2
%N 4
%D 11 2020
%M 33345928
%F 8.679
%R 10.1016/j.ajogmf.2020.100220
%X This study aimed to determine the optimal cervical priming regimen before surgical abortion up to and including 13+6 weeks' gestation.
Embase, MEDLINE, and the Cochrane Library were searched for publications up to February 2020. Experts were consulted for any ongoing or missed trials.
This study included randomized controlled trials published in English after 2000 that compared the following: (1) mifepristone and misoprostol against each other, placebo, or no priming; (2) different doses of mifepristone or misoprostol; (3) different intervals between priming and abortion; or (4) different routes of misoprostol administration.
Risk of bias was assessed using the Cochrane Collaboration checklist for randomized controlled trials, and data were metaanalyzed in Review Manager 5.3. Dichotomous outcomes were analyzed as risk ratios using the Mantel-Haenszel method, and continuous outcomes were analyzed as mean differences using the inverse variance method. Fixed effects models were used when there was no substantial heterogeneity (I2<50%), random effects models were used for moderate heterogeneity (I2≤50% and <80%), and evidence was not pooled when there was high heterogeneity (I2≥80%). Subgroup analyses were undertaken based on parity where available. The overall quality of the evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation.
A total of 18 randomized controlled trials (n=8538) were included and showed the following: decreased incomplete abortion rate (risk ratio=0.44; 95% confidence interval, 0.21-0.9) and force required to dilate the cervix (mean difference= -7.08 N; 95% confidence interval, -11.67 to -2.49) and increased preoperative bleeding (risk ratio=5.90; 95% confidence interval, 5.08-6.86) with misoprostol compared with no priming; decreased preoperative bleeding when sublingual misoprostol was given 1 hour before abortion compared with 3 hours before (risk ratio=0.14; 95% confidence interval, 0.03-0.56); and increased force required to dilate the cervix (mean difference=14.3 N; 95% confidence interval, 2.13-26.47) when mifepristone was given 24 hours before abortion compared with 48 hours before. The quality of the evidence base was limited by low event rates and risk of bias in included studies.
Cervical priming with misoprostol decreases the force needed to dilate the cervix for first trimester surgical abortion and reduces the risk of incomplete abortion. Considered alongside clinical expertise, this evidence supports the use of routine cervical priming before first trimester surgical abortion with 400 µg misoprostol or, if misoprostol cannot be used, 200 mg oral mifepristone.