When Will My Baby Arrive?
Babies are born on nature's timetable, but you can make a good estimate of your due date based on last menstrual period.
About due dates: Due dates are an estimate and it is normal for babies to arrive within two weeks of the due date - either two weeks "early," or two weeks "late."
Remember, babies arrive on nature's timetable, and precise calculations are difficult due to differences in the length of menstrual cycles, etc. Your physician is your best source of information about your unique pregnancy and your labor and delivery.