Many people wonder, "How long do sperm live?" After ejaculation, sperm start their journey up through the vagina, then to the uterus, and finally up to the fallopian tubes to wait for the egg. On average, sperm have the ability to fertilize an egg for 12 to 48 hours after ejaculation; in rare cases, some "super sperm" live for about 72 hours.
What Is Happening Inside Your Body When You're 3 Weeks Pregnant?
When you are 3 weeks pregnant, a ripened egg has been released from an ovary and drawn into the fallopian tube, where conception occurs. There are 350 million sperm in the average ejaculation that have a chance at making it into the fallopian tube. The sperm that actually make it into the fallopian tube can wait up to three days for an egg. When the sperm penetrates an egg, fertilization (conception) occurs. The fertilized egg is now called a zygote, which immediately begins dividing into identical cells as it floats down the fallopian tube to the uterus. The zygote then implants into the lining of the uterus. You are now pregnant.