**6. Conclusions**

Endometritis is the butler of the equine reproduction, and it is the main suspect in all cases of impaired fertility of the mare. Every year the literature is enriched by new interesting reports about this subject, which throw even more light on the knowledge of its pathogenesis. The events occurring during the uterine inflammatory response are complex and intertwined. A thorough understanding of the physiological response to uterine contamination, which is necessarily correlated with the act of the insemination, may allow timely identification of susceptible mares, in which these mechanisms get jammed within the first hours after breeding. Type and dose of treatments, as well as timing of administration, should be correctly targeted towards susceptible and/or affected mares to optimize the results and reduce the cost and the resources used. Continued research is welcome in this area of equine medicine, so that treatment strategies can be further improved.
