A major consideration is whether the sperm were compromised prior to cryopreservation (“freezing”). For example, the older the male the higher the rate of DNA mutation. Also, if the patient had an illness ranging from the common cold to a terminal illness, sperm quality can decrease. Sitting in hot tubs, smoking cigarettes or marijuana, and prolonged inactivity (sitting) are all known to decrease sperm quality. With that being said, studies indicate that frozen sperm can successfully be used to create a child 20-30 years after it was frozen .