The effect of endocervical and catheter bacterial colonisation during fertilisation and embryo transfer (IVF-ET) on IVF success rate among asymptomatic women: a longitudinal prospective study.

The adverse effects of bacterial contamination during fertilisation and embryo transfer (IVF-ET) have been studied previously. However, data on asymptomatic women with positive bacterial culture and their IVF outcome are lacking. This prospective longitudinal study was conducted on 74 women undergoing IVF-ET, of whom specimens from the endocervix and ET catheter were taken and sent to a laboratory for microbiological assessment. Then, patients were followed up for evaluation of chemical pregnancy (β-HCG > 25 mIU/mL) and clinical pregnancy (detected foetal heartbeat). The findings revealed that there was no significant difference in terms of biochemical (35.4% vs. 19.2%, = .116) and clinical pregnancy rate (25.0% vs. 15.4%, = .257) among ET catheter culture positive and negative women. This finding allows us to conclude that the positive culture in the absence of clinical signs of infection may not increase the risk of implantation failure.Impact Statement There is growing evidence indicating that endometritis may decrease the endometrial receptiveness in fertilisation (IVF) cycles; however, there is a paucity of knowledge regarding IVF outcomes when the bacterial culture of embryo transfer (ET) catheter is positive. The present study demonstrates that positive ET catheter culture in asymptomatic women does not increase the risk of IVF failure. Positive-culture, , may not be associated with poor IVF outcomes and further studies should be undertaken on this topic in various clinical settings using different protocols.