Pain Significantly Reduces Sexual Motivation in Female, But Not Male, Mice

Chronic pain is a debilitating condition frequently associated with various comorbidities, including sexual dysfunction, which significantly impacts quality of life and relationships. This widespread clinical observation suggests that pain can profoundly diminish libido. However, the precise biological mechanisms underlying this link, particularly whether there are inherent sex-specific differences in how pain affects sexual motivation, have remained largely unexplored. This study specifically addresses whether pain-induced reductions in sexual motivation have a direct biological basis and manifest differently between sexes in a controlled experimental setting.

The core finding revealed a striking sex difference: inflammatory pain significantly reduced sexual motivation in female mice. This reduction was consistently observed across all experimental conditions, regardless of whether the pain was induced in genital or nongenital regions. In stark contrast, male mice subjected to identical pain stimuli exhibited unimpeded sexual motivation, demonstrating no significant impairment in their sexual behavior. Importantly, these sex-specific effects on libido were evident even when there were no discernible sex differences in general pain-related behaviors, suggesting a direct and specific impact on sexual drive rather than overall pain sensitivity. > The most critical discovery was that the pain-induced decline in female sexual behavior could be completely reversed or rescued through pharmacological intervention. Treatment with the analgesic pregabalin, as well as the libido-enhancing compounds apomorphine and melanotan-II, effectively restored sexual motivation in the pain-affected female mice, highlighting a clear mechanistic link.