The rapid effects of steroids on spermatozoa have been demonstrated for the first time more than three decades ago. Progesterone (P), which is present throughout the female genital tract with peaks of levels in the cumulus matrix surrounding the oocyte, has been shown to stimulate several sperm functions in vitro, including capacitation, hyperactivation, chemotaxis and acrosome reaction (AR). Besides an increase of intracellular calcium, P has been shown to activate other sperm signalling pathways including tyrosine phosphorylation of several sperm proteins. All these effects are mediated by extra-nuclear pathways likely involving interaction with molecules present on the sperm surface. In particular, the increase in intracellular calcium ([Ca²⁺]_i) in spermatozoa from human and several other mammalian species is mediated by the sperm specific calcium channel CatSper, whose expression and function are required for sperm hyperactive motility. P-mediated CatSper activation is indeed involved in promoting sperm hyperactivation, but the involvement of this channel in other P-stimulated sperm functions, such as AR and chemotaxis, is less clear and further studies are required to disclose all the involved pathways. In human spermatozoa, responsiveness to P in terms of [Ca²⁺]_i increase and AR is highly related to sperm fertilizing ability in vitro, suggesting that the steroid is a physiological inducer of AR during in vitro fertilization. In view of their physiological relevance, P-stimulated sperm functions are currently investigated to develop new tools to select highly performant spermatozoa for assisted reproduction.

三十多年前，首次证明了类固醇对精子的快速作用。孕酮（P）存在于整个女性生殖道中，卵母细胞周围的积丘基质中的水平达到峰值，已被证明可在体外刺激多种精子功能，包括获能，过度激活，趋化性和顶体反应（AR）。除了增加细胞内钙外，P还被证明可以激活其他精子信号传导途径，包括几种精子蛋白的酪氨酸磷酸化。所有这些作用均由核外途径介导，可能涉及与精子表面分子的相互作用。特别是细胞内钙（[Ca ²⁺ ] _i精子特异的钙通道CatSper介导人类和其他几种哺乳动物的精子中的精子，其表达和功能是精子活动过度所必需的。P介导的CatSper激活确实与促进精子过度激活有关，但该通道与其他P刺激的精子功能（如AR和趋化性）的关系尚不清楚，因此需要进一步研究以揭示所有相关途径。在人类精子中，以[Ca ²⁺ ] _i表示的对P的反应性增加，AR与体外精子受精能力高度相关，这表明类固醇是体外AR的生理诱导剂。受精。考虑到它们的生理相关性，目前正在研究P刺激的精子功能，以开发新的工具来选择高性能的精子用于辅助生殖。