Sperm can live inside a woman's reproductive system for up to about 5 to 7 days under optimal conditions. The survival time depends on the environment inside the female body, particularly the presence of fertile cervical mucus, which protects and nourishes the sperm. Without this favorable environment, sperm typically survive only a few hours to a day. The cervical mucus becomes more conducive to sperm survival around ovulation, helping sperm to live longer and increasing the chances of fertilization during the fertile window. Outside the female body, sperm usually die within minutes due to dryness and exposure to air.