This past week, I had a surprising experience regarding due dates. Everyone knows that due dates are never completely exact, but they can often be determined with a reasonable degree of certainty by calculating the date of your last menstrual period. There are things that can affect that calculation, though, causing the due date to be rather far off.
One thing that can happen is that many people have no idea what the date was when they started their last menstrual period. Some people do, usually those are people who have been keeping track of their cycles so that they can get pregnant. I happened to be keeping track of my cycles because we knew that we wanted to get pregnant again soon so that our children would be fairly close in age. So, an incorrect cycle date can throw things off a bit.
Irregular cycles are another thing that can affect the accuracy of a due date calculation. My cycle had returned only a few months before this pregnancy started and there was a huge variation in the number of days in each cycle. This made it rather difficult to determine a due date in the first place, and my midwives spent quite a bit of time doing the math and trying to figure out a good estimate.
A third thing that can affect the accuracy of a due date calculation is whether or not you are nursing another child when you become pregnant. My twenty eight month old son is still nursing now, so of course he was nursing when I got pregnant.
How far off was my due date? Last Friday I thought I was almost 36 weeks pregnant. During an ultrasound, the doctors looked at measurements from my first ultrasound at 26 weeks and compared them to the ones that they were taking that day and determined that I was almost 40 weeks pregnant as of that day.
Some people may have been a little freaked out upon finding that the baby that they were expecting in a month would be arriving in a day or so. I was overjoyed because at the same time it was determined that I had developed preeclampsia and needed to deliver the baby the next day. It was a relief to know that I was delivering a baby who was ready to be delivered and that he was healthy. Blake is already almost a week old – and to think that he was not “due” to arrive until the middle of next month!