The fertilization of the ovum happens when the sperm unites with the ovum. Also known as fertilization, it is the beginning of pregnancy. However, the fact that the egg has been fertilized does not guarantee that there will be a pregnancy.
In order for you to get pregnant, the fertilized egg needs to go through implantation, which is the process where the egg attaches to the lining of the uterus. This is the place where the pregnancy will develop from now on.