Week 01: Your pregnancy
Your baby's growth: The pregnancy timetable
Pregnancy has an average length of 40 weeks. The first week is your period, and the very end of the second week marks the release of the egg—ovulation. The egg is fertilized early in the third week and typically implants in the uterus 6-12 days after ovulation. This means that using this dating method, you actually get pregnant during the third or early fourth week.
You can calculate your due date by adding seven days and subtracting three months from the first day of your last period.
What's happening with you
This week is your menstrual period. If you become pregnant two weeks or so from now, menstruation will be the point from which your pregnancy will be dated. Pregnancy is timed this way because most women don't know the precise moment they have ovulated or conceived. But most do remember the first day of their last menstrual period.