Pet peeve: how long pregnancy ACTUALLY is

Yesterday marked exactly one month until my due date. Which means that technically when people ask when I'm due, I could say, "The 19th," and not need to qualify it with a month, because it's the NEXT 19th. Yikes! I think I'm going to keep saying "next month" until we actually get to January, though. But still. Less than a month away.

Speaking of pregnancy months, here is a pet peeve of mine: it feels like every pregnant woman I know complains that nobody ever told her that pregnancy is actually TEN months long, not nine (which, given that everybody seems to complain about this, makes it surprising that they all seem so shocked by this apparent revelation, since you would think they would have heard each other complaining about it in the past).

But my real issue is this: pregnancy is NOT ten months long. It's not really even quite nine months long. Let me break this down for you. Those of you who have been pregnant before likely know this, but I didn't know some of it until I myself got pregnant, so let's start at the beginning.

Pregnancy is measured as being 40 weeks long. As in, when you hit 40 weeks, that is your due date. BUT, the 40 weeks are counted from the date of your last menstrual period, NOT from the date of ovulation or conception (and those can actually happen a day or so apart as well). Most women ovulate at least two weeks after the first day of their period. So for those first two weeks of "pregnancy," you are NOT actually pregnant. You are only considered to have been pregnant retroactively, but during those first two weeks you could easily have avoided getting pregnant, by using birth control or not having sex (or not going through fertility procedures, and so on--the point is, during those two weeks, the pregnancy was not a foregone conclusion).

Got it? For the first two of the 40 weeks, you were NOT pregnant, even though that time is counted as part of your pregnancy.

So for one thing, pregnancy is actually only 38 weeks from conception to due date. Though sometimes it pushes closer to 40 weeks again if the baby comes late.

But let's just say, for a second, that pregnancy really is exactly 40 weeks long. THAT IS STILL NOT TEN MONTHS. That is approximately ten LUNAR months, but we DO NOT COUNT TIME IN LUNAR MONTHS. If we did, we would say that a year is 13 months long, but we don't. We say it is 12 months long, because that's what our calendars say--all of our months except February are longer than four weeks.

To be exact, a 30-day month is 4.29 weeks long, and a 31-day month is 4.43 weeks long. Let's average those out and round down a tad to account for February (or we could divide 365 by 12, and then divide that by 7, which would give us the same result) and say that a month is, on average, 4.35 weeks long.

So, if we count pregnancy as 40 weeks and a month as 4.35 weeks, that would make pregnancy about 9.2 months long. And if we count the actual time that you are pregnant, assuming an on-time delivery, as 38 weeks, that makes pregnancy about 8.7 months long. NOT EVEN NINE MONTHS.

In case your eyes crossed when I started using decimal points, I charted my cycle the month I got pregnant, so I have exact dates that I can use to demonstrate this more concretely:

My last period started on April 13. I ovulated on April 26. My due date is January 19 (though some calculators/wheels list it as January 18, which I think is actually more accurate--but is not what's in my chart). So, let's see. April 13 to January 19? NOT ten months. April 26 to January 19? DEFINITELY not ten months.

I KNOW, the point pregnant women are trying to make is that pregnancy is long and often feels even longer, but it drives me NUTS when they try to express this by talking about how it is ten months long. IT IS NOT TEN MONTHS LONG.

Nine months is long enough that we all have PLENTY of legs to stand on when it comes to complaining about the misery of the experience. Let's not all undermine our credibility by exaggerating just to make our plights sound THAT much more dire.