Pregnancy 2nd week: The Fertilization
The thing with the pregnancy weeks is partial for laymen misleading. For the computation of the duration of the pregnancy, which covers 40 weeks on basis of this calculation, as starting point the first day of the last Menstruation is consulted. The actual pregnancy begins therefore only in the 2nd week.
In the second pregnancy week maturing the egg cells in fruit caps takes place. In a time window, which moves between two to four days, the egg cell is available for fertilization. Only in this time the outside covering for sperm cells is permeable. A Spermium needs to penetrate twenty to thirty minutes over into the egg cell. In the 12 to 15 hours after this procedure the cell cores of the egg cell and the Spermiums merge. Already in this early stage the leavable characteristics are specified. One calls the fertilized egg starting from this time Zygote. Already during the journey over the Eileiter to the uterus the division of the fertilized cell begins.
Pregnancy 2nd week: Cell division and nidation
About every 12 hours takes place a new division of the fertilized egg cell. After only four days already 16 new cells formed in this way. This is formed in the placenta and is responsible for the preservation of the pregnancy. Also the hormone progester is formed, which prevents that it comes to further ovulations. In the same course the menstrual bleeding is missing with the pregnant woman.