Pregnancy Pregnancy and Preparations Pregnancy Process
Pregnancy and Preparations
A man’s sperm and a woman’s egg meets in the Fallopian tubes through sexual intercourse to produce a fertilized egg. This egg moves and is implanted on the uterine wall.
The sperm that went into the vagina through ejaculation reaches the oviduct by moving its long tail. An egg must be fertilized within 12 to 24 hours after the ovulation. Sperm sustains its fertilization capacity for about 48 to 72 hours after being ejaculated. Thus either sperm reaches the destination by the time an egg is absorbed into the oviduct or an egg enters the oviduct while sperm is alive to fertilize.
The number of sperms that reach the oviduct out of the hundreds of billions of ejaculated sperms is only 150 to 200. Moreover, only one sperm meets and is combined with an egg, which means that most of the sperms die before they reach the uterus. Upon fertilization, an egg creates a thick membrane on the surface to prevent other sperms from entering.
It takes about three to four days for the fertilized egg to reach the uterus while continuing the cell division. By the time it arrives, it is divided into 12 to 58 cells, which is called the morula stage. It keeps dividing itself to enter the blastocyst stage. In this stage, it is divided into an area that grows into a baby and things that help the baby grow, such as the placenta, umbilical cord, amniotic fluid, and amnion. The fertilized egg that has reached the uterus membrane melts the surface and gradually buries itself into it, which is called implantation. It usually takes about a week for implantation to take place after fertilization.