The home pregnancy test says that you are pregnant. You’ve called the doctor and made an appointment, but you can’t wait to hear what he says. How can you tell when your due date is? While there are plenty of online calculators, there’s nothing quite like thumbing through a calendar in anticipation of circling the big day. It’ll only take you a few minutes to figure out the approximate day of conception and tell what your pregnancy due date is.
Step 1
Pinpoint the first day of your last menstrual period. If you don’t track it on a calendar or if you have irregular periods, think back to what you were doing or where you were when you started and remember the date by association.
Step 2
Calculate your due date by adding 280 days from the first day of your last menstrual cycle. Ovulation and conception usually occur two weeks after the onset of your period, and an average pregnancy lasts 266 days; 266 plus14 equals 280.
Step 3
Convert the days until you are due into weeks by dividing 280 days by seven days (one week); an average pregnancy lasts 40 weeks.
Step 4
Count 40 weeks from the first day of your last menstrual period to arrive at your due date.
