How does the pregnancy held? How does a woman get pregnant?
When the semen is collected at the opening of uterus, then the millions of sperms swim towards the fallopian tubes where a mature egg in either of the tube is present. The sperms more with the speed of 1/10 of an inch per minute and then reach at their destiny in approximately 45 minutes. The most powerful and strong sperms reach to the ovum becomes stronger again and the other sperms that do not become able to penetrate get destroyed.
The penetrating sperm's head fuses with the ovum nucleus, and after fertilization, it becomes zygote. This process is called as pregnancy.