Sperm freezing, also known as sperm cryopreservation, is a fertility preservation procedure that allows sperm cells to be stored at ultra-low temperatures for future use. Using modern cryopreservation techniques, sperm can maintain viability for decades, providing multiple reproductive opportunities when the time is right to start or expand a family. Sperm are frozen and stored in liquid nitrogen tanks at –196°C, where cellular activity is halted and quality is preserved. The process begins with a specialized andrological evaluation. A comprehensive semen analysis (seminogram) is performed to assess sperm concentration, motility, and morphology, along with hormonal testing such as testosterone, FSH, and LH when indicated. This evaluation helps determine baseline sperm quality and guides recommendations on the number of samples to freeze. Sperm freezing is commonly recommended before vasectomy, cancer treatments (such as chemotherapy or radiation), urological procedures that may impact fertility, in cases of progressive decline in sperm quality, or for individuals who wish to postpone parenthood while preserving current sperm quality. Prior to sample collection, sexual abstinence of 2–5 days is recommended to optimize sperm quantity and motility. On the day of the procedure, the semen sample is obtained through masturbation in a private and comfortable setting at the clinic. The sample is processed within one hour to ensure optimal viability. In the laboratory, sperm are prepared and combined with specialized cryoprotectors that protect cells during freezing. A controlled freezing protocol is used to gradually lower the temperature and prevent cellular damage. The prepared samples are then stored in clearly identified liquid nitrogen tanks with continuous monitoring systems. The number of samples recommended for freezing depends on initial semen quality and future reproductive plans. For normal parameters, freezing 3–5 samples is often sufficient, while reduced sperm quality may require 5–10 samples. Each frozen sample typically contains approximately 0.5 ml with millions of sperm cells. Modern cryopreservation techniques achieve post-thaw survival rates of approximately 60–90%, depending on the initial quality of the sample. Thawed sperm are evaluated for survival and quality and can be used in future fertility treatments. When sperm quality is adequate, they may be used for intrauterine insemination, and for any level of quality, they can be used with IVF and intracytoplasmic sperm injection (ICSI). Sperm freezing provides flexibility and long-term reproductive security, allowing individuals to preserve fertility today and use their sperm when they are ready, under carefully monitored and secure storage conditions.