In its most basic description, human fertility can be summarized as requiring only a few key elements. Hormones ebb and flow to create a pattern of orderly monthly uterine bleeding known as the menstrual cycle.
Towards the middle of the cycle, an egg is released from the ovary in a process called ovulation. The egg is picked up by a structure called the Fallopian tube, where it waits for sperm. During and for some time after intercourse, sperm swim from the vagina into the uterus, then into the Fallopian tube where fertilization of the egg occurs.
The fertilized egg grows and travels into the uterus, where it grows into the wall of the uterus to set up an early pregnancy.
