Originally Posted by patrickBOOTH
How good are their forecasts? I'm curious. That's very specific, I'd like to see some stats. You know Root Mean Squared Error and shit. Its one thing to say "the beginning of March" another to give you a day. I'd call bullshit on that pompous prick!
Due dates are useful from a medical perspective, because they can be used to create benchmarks for fetal development (i.e. "at approximately xx weeks, we should be seeing these features, and we need to monitor more closely if we don't"). However, they're basically useless from a "my baby will come on x/x/xx" perspective. Something like 95% of kids won't be born on their due date. In fact, only like 80% are born within 37-42 weeks of gestation, and there's a two-week window for what's considered "full term" with another couple weeks on each side for what's considered "early/late term."
So, basically, a due date is the day that's a best guess based on a few factors, but the baby almost certainly isn't coming that day. It's very much a ballpark estimate. If the doctor is saying 3/8/15, what they really mean is, "plan to have a new baby sometime between mid February and mid March."