Background: Different surgical methods for termination of pregnancy have evolved over the years: Dilatation and curettage, power operated vacuum aspiration, manual vacuum aspiration (MVA) or hysterotomy. Local or general anaesthesia is used for all methods. Preabortion medical or mechanical cervical preparation may reduce the incidence of cervical or uterine injuries.
Objectives: To compare the safety and efficacy of different surgical methods for first trimester abortion.
Search strategy: The Cochrane Controlled Trials Register has been searched. A search of the reference lists of identified trials was performed. An additional MEDLINE search was done using the Internet search service Pub Med.
Selection criteria: Randomised controlled trials comparing different surgical methods for first trimester abortion were eligible.
Data collection and analysis: Trials under consideration were evaluated for methodological quality and appropriateness for inclusion. Three trials were included, resulting in 2 comparisons: vacuum aspiration versus dilatation and curettage and flexible versus rigid vacuum aspiration cannula. Results are reported as odds ratio for dichotomous data and weighted mean differences for continuous data.
Main results: There were no reports of maternal deaths and cases of uterine perforation in the trials identified. Vacuum aspiration versus dilatation and curettage: There were no statistically significant differences for excessive blood loss, blood transfusion, febrile morbidity, incomplete or repeat uterine evacuation procedure, re-hospitalisation, post operative abdominal pain or therapeutic antibiotic use. Duration of operation was statistically significantly shorter with vacuum aspiration compared to D&C in both gestational age subgroups : < 9 weeks: weighted mean difference (WMD) -1.84 minutes, 95% confidence interval (CI) [-2.542,-1.138]; =/> 9 weeks: WMD -0.600 minutes, 95% CI [-1.166,-0.034]). Flexible versus rigid vacuum aspiration cannula: There were no statistically significant differences with regard to cervical injuries, febrile morbidity, blood transfusion, therapeutic antibiotic use, or incomplete or repeat uterine evacuation procedure.
Reviewer's conclusions: The included studies do not indicate a preference of providers for one or the other method. The trials included are small and lack power to to present meaningful differences for rare outcomes between the groups. outcomes such as women's satisfaction, the need for pain relief or surgeons preference for the instrument have been inadequately addressed. No data outcomes, such as fertility after surgical abortion, are available.