Intrauterine adhesion prevention after hysteroscopy: a systematic review and meta-analysis

BACKGROUND: Despite years of studies evaluating prevention strategies for intrauterine adhesion formation after operative hysteroscopy, it is still unclear which strategies are most effective. OBJECTIVE: The objective of the study was to perform a systematic review and meta-analysis to evaluate the effectiveness of postoperative prevention strategies on intrauterine adhesion formation following operative hysteroscopy. STUDY DESIGN: Literature searches were conducted in MEDLINE, Embase, ClinicalTrials.gov, and Cochrane Library databases. Inclusion criteria were published randomized controlled clinical trials from 1989 to 2014 comparing any postoperative preventative measures of intrauterine adhesion after hysteroscopy. The main outcome measure was a reduction in postoperative intrauterine adhesion. Heterogeneity of the studies was evaluated using a Q test and an I 2 index. Analyses were performed using a random-effects model with outcome data reported as relative risk with 95% confidence interval. RESULTS: Twelve studies were included in the systematic review. Eight studies compared similar treatment methods and were included in the meta-analysis. Three studies evaluated hyaluronic acid gel, of which 2 reported a significant decrease in intrauterine adhesion with treatment. The meta-analysis demonstrated a significant reduction of intrauterine adhesion when using hyaluronic acid gel. Two studies evaluated polyethylene oxide-sodium carboxymethylcellulose gel, 1 of which demonstrated a decrease in intrauterine adhesion with treatment. A meta-analysis showed a significant reduction of intrauterine adhesion with polyethylene oxide-sodium carboxymethyl cellulose gel. However, these 3 studies demonstrating a benefit of the gels in preventing adhesion formation were all conducted by the same research group. Other research groups have not confirmed these results. A sensitivity analysis excluding these trials from this single group demonstrated no benefit to adhesion prevention with either gel formation. Three studies investigated oral estrogen therapy after hysteroscopy and found no difference in intrauterine adhesion. A meta-analysis showed no decrease in intrauterine adhesion with estrogen therapy after hysteroscopy. Data were lacking to perform meta-analyses on the use of intrauterine balloon, intrauterine device, and other adhesion prevention barriers in preventing intrauterine adhesion. CONCLUSION: There was a lack of definitive evidence to conclude that any treatment is effective in preventing posthysteroscopy uterine adhesion formation. The available literature has significant heterogeneity and a high risk of bias, making any definitive conclusions difficult.