The human reproductive system is responsible for producing offspring. During sexual intercourse, the semen from male is discharged in the vagina. The sperms will begin moving up to the uterus reaching the fallopian tube, During the travel most of the sperms will die while climbing up the fallopian tube, only one sperm will enter the ovum and can remain alive for only 12 hours. In this time, if it meets ovum which will lead to fertilization. This zygote (fertilized egg) will form in an embryo from which will enter gestation period. It is around 9 months in time for the woman to give birth. This process leads to conception and eventually the birth of a baby. Following childbirth, the female body undergoes changes to return to its original state.