**7. Conclusion**

It is clear that *E. coli* has an important role in causing male infertility associated with genital tract infections. The main mechanism postulated for male infertility by *E. coli* is the profound damage to different sperm processes and function, either by direct contact and/or through secreted toxins.

While today there is a consensus that *E. coli* is an important causal agent of MGTI that may actually cause infertility, from the latest evidence presented above, it is clear that this would not be completely true for all UPEC. Due to these differences among the various strains, it seems important to develop molecular studies that can clarify what specific features of the *E. coli* strains are associated with the pathogenic effects on sperm or with an aggressive inflammatory response this point should be followed.

To date, there have only been a few studies at the molecular level to try to explain how *E. coli* causes infertility.

Knowledge of the molecular mechanisms by which *E. coli* damages sperm will make it pos‐ sible to take measures to avoid its consequences on the fertilizing potential of men.

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