Hydrosalpinx and pregnancy loss: a systematic review and meta-analysis.

RESEARCH QUESTION: What is the association between hydrosalpinx and pregnancy loss and the effects of treatment for hydrosalpinx? DESIGN: A systematic review and meta-analysis was conducted to investigate the risk of pregnancy loss, and the benefit of treatment in women with hydrosalpinx. Searches were conducted on MEDLINE, Embase, the Cochrane Library and Web of Science. RESULTS: A meta-analysis of 14 observational studies showed a 74% relative increase in the risk of pregnancy loss in women with hydrosalpinx compared with women without hydrosalpinx (relative risk [RR] = 1.74, 95% confidence interval [CI]: 1.43, 2.12, P< 0.00001, I2 = 31%). Pooling of risk ratios from seven randomized trials and six observational studies of treatment of hydrosalpinx showed a reduction in pregnancy loss of approximately half when compared with no treatment (RR = 0.46, 95% CI: 0.34, 0.63, P <0.00001, I2 = 0%). CONCLUSIONS: This evidence suggests that the presence of hydrosalpinx increases the risk of pregnancy loss and that treatment can reduce this risk. However, in all studies apart from one, participants conceived through IVF so the evidence is less certain for women conceiving naturally. Further research should consider whether women with recurrent miscarriages should have routine screening for hydrosalpinx.