The release of an egg from the body begins with ovulation, which occurs after the end of menstruation when estrogen gradually rises and the egg cell begins to develop over a period of about a week or so. As the follicle matures and moves toward the surface of the ovary, the epidermal layer encasing the follicle becomes thinner and thinner, and the intrafollicular fluid becomes more and more abundant, resulting in a gradual increase in pressure within the follicle, and ultimately the follicle ruptures and releases the egg. After the egg is released it will be picked up by the umbrella of the fallopian tube on the same side, and returned to the fallopian tube to wait for sperm. If encountered sperm will form a fertilized egg to develop into a fetus, if not encountered sperm egg will die in about two days, with the uterine cavity secretion out of the body, the uterine cavity secretion is one of the components of the leukorrhea, that is, the death of the egg is with the leukorrhea out of the body. However, since the egg cell is small and mixed in the leukorrhea, it is not easy to detect even if it is discharged.