Male infertility affects many couples, with sperm maturation in the epididymis playing a crucial role. As sperm travel through different parts of the epididymis, their composition changes, affecting their ability to fertilize an egg. The epididymis creates a special environment for sperm maturation, with genetic factors influencing sperm quality. Small RNA molecules in sperm also change during this process and can impact embryo development. Understanding how the epididymis helps sperm mature is important for addressing male infertility.