The Sperm's Long Journey. A man may ejaculate 40 million to150 million sperm, which start swimming upstream toward the fallopian tubes on their mission to fertilize an egg. Fast-swimming sperm can reach the egg in a half an hour, while others may take days. The sperm can live up to 48-72 hours. Only a few hundred will even come close to the egg, because of the many natural barriers that exist in a woman's body.
9.4 Giving birth. Normal delivery. Children that are born between the 36th and 39th week (38 and 41 weeks after the LMP) are considered as being normal deliveries. Statistically, only 2/3 of all children are born within the 3 weeks around the calculated date of birth and around 80 % within a month around the predicted date of birth.
There are 4 weeks and 2-3 days normally. 52 weeks in a year, not just 48. So if you are pregnant for the exact amount of time that you should be then you are pregnant for 9months and about a week. A majority of mommy's give birth a week before to a week after their due date which still ranges in the 9 month range. But we are not pregnant for 10 months. Your body stops receiving nutrients in the womb at 40 weeks which is why they will induce at 41 weeks of you haven't given birth yet.