**Author details**

To date, the assisted reproductive technology literature describing attempts to alter the microbiome in the reproductive tract in order to impact outcomes has been operating on a rudimentary understanding of this complex environment at best. However, this approach, although perhaps to blunt a tool at present, may indeed be an important key to altering both the microbiome and subsequently the immune system as we further explore enhancement of

Knowledge regarding the interactions between the microbiome and the human reproductive axis is growing rapidly. A deeper understanding of normal physiology, identification of different dysbioses, and characterizing the microbiome's impact on reproductive outcomes promise meaningful enhancements in clinical care. While much has been learned since the early contributions of Semmelweis, the most insightful and powerful findings may lie just

Although the reproductive tract microbiome remains relatively poorly understood in terms of its relationship to reproductive outcomes, there is a long history of attempting to influence it with the use of prophylactic antibiotics at the time of procedures during ART. This has been a practice ingrained since 1978, when it was suggested that contamination during ART procedures could negatively affect outcomes [101]. Because antiseptics, such as povidone iodine, can have a negative impact on embryos, antibiotics were turned to as a way of

A common time for antimicrobial prophylaxis is at the time of ET. Given the concern for colonization of the transfer catheter tip with microbiota from the upper genital tract, antibiotics have been proposed as a way to decrease inoculation of the uterine cavity and thereby increase pregnancy rates. Despite this widespread practice, relatively little data exist to support or

A recent Cochrane review analyzed randomized controlled trials in the literature that investigated antibiotics at ET [103]. Only four potential studies were identified, of which three were excluded. The remaining study reported on clinical pregnancy rates as the primary outcome. Although administration of antibiotics reduced microbial contamina‐ tion as defined by culture of ET catheter tips, the clinical pregnancy rate was 36% in those receiving antibiotics and 35.5% in those not receiving antibiotics (odds ratio 1.02, 95% confidence interval 0.66–1.58) [104]. The reviewers concluded that more evidence is needed

reproductive competence in assisted reproductive technology.

**5.6. Conclusion**

124 Genital Infections and Infertility

ahead [100].

**6. Antimicrobials and ART**

manipulating the microbiome [102].

with live birth as the primary outcome.

refute antibiotic use.

Reza Peymani\* and Alan DeCherney

\*Address all correspondence to: rpeymani@hotmail.com

National Institutes of Health (NIH), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Fertility and Infertility Branch, Bethesda, USA
