Pyometra is a major reproductive disorder affecting female cats. Characterized by the accumulation of purulent exudate in the uterus, it can lead to severe and potentially fatal complications. This pathology primarily occurs in adult cats during diestrus, but can also affect younger felines, often due to inappropriate administration of hormonal medications. While the etiopathogenesis of pyometra is better understood in bitches, few studies have addressed the molecular factors involved in feline pyometra. Therefore, this review aims to provide an up-to-date and comprehensive discussion of pyometra in cats, focusing on the regulation of molecular factors described in this species, including hormonal, redox, immunological, and growth factors. Understanding the regulation of these factors in pyometra is crucial for elucidating its pathogenesis in domestic cats and for improving diagnosis and identifying novel therapeutic approaches.