Fertilization: Sperm Penetrates Egg. It takes about 24 hours for a sperm cell to fertilize an egg. When the sperm penetrates the egg, the surface of the egg changes so that no other sperm can enter. At the moment of fertilization, the baby's genetic makeup is complete, including whether it's a boy or girl.
Implantation bleeding is an early sign of pregnancy and only experienced by 1/3 of women. Discover when and what to look for as a sign of implantation. Implantation bleeding is an early sign of pregnancy and only experienced by 1/3 of women.
Best Answer: Implantation bleeding (if you get it) usually occurs between 6 to 12 days past ovulation. HCG doesn't generally start being produced until after implantation so even with the most sensitive test you usually need to wait at least 2 days.est Answer: Implantation bleeding (if you get it) usually occurs between 6 to 12 days past ovulation. HCG doesn't generally start being produced until after implantation so even with the most sensitive test you usually need to wait at least 2 days.