Surgical or medical abortion of pregnancies between 13+0 and 23+6 weeks' gestation? A systematic review and new NICE national guidelines

Background Abortion in the second trimester may be performed surgically or medically. The objective of this systematic review was to examine the effectiveness, safety and acceptability/satisfaction of surgical compared with medical abortion of pregnancy between 13(+0) and 23(+6) weeks' gestation for a new national guideline. Methods We searched Embase, Medline and the Cochrane Library on 4 March 2019. We included randomised controlled trials (RCTs; any size) and non-randomised comparative studies with n >= 100 in each arm, published in English from 1985. Risk-of-bias was assessed using the Cochrane Collaboration checklist for RCTs. Meta-analysis of risk ratios (RRs) used the Mantel-Haenszel method. The quality of the evidence was assessed using GRADE. Results Two RCTs (n=140) were included. 'Incomplete abortion requiring surgical intervention' was clinically significantly higher with medical than surgical methods (RR=4.58, 95% CI 1.07 to 19.64). 'Abortion completed by the intended method' was statistically, but not clinically, significantly lower after medical than surgical methods, but was marked by high between-study heterogeneity (RR=0.88, 95% CI 0.79 to 0.98). To the extent that 'haemorrhage requiring transfusion/>= 500 mL blood loss', 'uterine injury', 'cervical injury requiring repair' and 'infection reported within 1 month of abortion' were reported, they did not differ significantly between methods. Depending on measurement method, 'patient satisfaction/acceptability' was either clinically significantly higher or comparable after surgical than medical methods. The quality of this evidence was limited by low event rates and attrition bias. Conclusion Based on this evidence and consensus, women should be offered the choice of medical or surgical methods of abortion between 13(+0) and 23(+6) weeks' gestation, unless not clinically appropriate.