The research of lactylation in the field of reproduction†.

Lactate, once considered merely the product of glycolysis, is now recognized as both a metabolic fuel and a signaling molecule with broad physiological and pathological roles. The landmark discovery of lysine lactylation in 2019 unveiled a novel, direct mechanism through which lactate regulates cellular function. This dynamic posttranslational modification, installed by "writers" enzymes and removed by "erasers," modulates the activity of histone and non-histone proteins, thereby influencing gene transcription, metabolism, and signal transduction. In reproductive biology, lactylation may represent an important regulator of fundamental processes including gametogenesis, embryo development, implantation, and placentation. Notably, aberrant lactylation is increasingly implicated in the pathogenesis of diverse reproductive disorders such as polycystic ovary syndrome, asthenozoospermia, ovarian cancer, preeclampsia, and recurrent pregnancy loss. This review systematically synthesizes current knowledge on the molecular mechanisms and functional significance of lactylation within the reproductive system, under both physiological and pathological contexts. Furthermore, we discuss the translational potential of targeting the lactylation pathway for novel therapeutic strategies and highlight key directions for future research.