1 Subtract eleven days from the total number of days to find the last fertile day in your cycle. 2  For example, if your longest cycle lasted 31 days, your last potentially fertile day in each cycle would be the 20th day in the cycle (31 - 11 = 20).
Why you shouldnât work up until your due date. I nearly gave birth to my son at work. Right there on the third floor of the sea foam-green AAA building on Van Ness Avenue, where I was working at the time. Luckily, my coworker Nino convinced me to go to the hospital when I told him that I was feeling crampy.
This method is more accurate than calculating through menstrual dates, he says, but it is not as good at dating your due date if you had assisted conception with fertility drugs and treatments. Doctors usually give women a range between 38 and 42 weeks of a pregnancy as the anticipated delivery time.