When the egg is released from the ovary, it moves inside the fallopian tube. If it meets up with a viable sperm and becomes fertilized, it continues traveling down the fallopian tube.
Fertilization usually happens within 12-24 hours after ovulation. After fertilization, the fertilized egg starts traveling down the fallopian tube toward the uterus.
If fertilization does not happen within 12-24 hours after ovulation, the egg dies off.
Implantation, the attachement of the fertilized egg to the uterus, happens on average about 9 days after ovulation/fertilization (between 6 and 12 days) and is required for the fetus to continue to grow.
The blood pregnancy test becomes positive 3-4 days after implantation, and the urine pregnancy test takes several days more.