Patient's question:
I have an itchy lower body, and my underwear is always yellow. What's going on? What happens if an egg is not fertilized?Doctor's answer:
As the fertilized egg begins to undergo mitosis, it moves toward the uterine cavity inside the fallopian tube, propelled by the movement of the fallopian tube and the action of cilia. Around the third day after fertilization, it divides into a solid cell mass composed of 16 cells, known as the morula (early blastocyst). By the fourth day after fertilization, the early blastocyst enters the uterine cavity and continues to divide and develop into a late blastocyst. Around the sixth to seventh day after fertilization, the process of the late blastocyst invading the endometrium after the disappearance of the zona pellucida is called implantation.