## 26 February 2008

### "One Giant Leap For Babykind"

One Giant Leap for Babykind, from the (Feb. 25?) New York Post.

A mother born February 29, 1980 is due to have a baby on February 29, 2008. (Her doctors have said they'll induce labor that day if it doesn't happen naturally.)

Now, one out of every 1461 days is a leap day; assuming that the events of a mother and a baby being born on that day are independent (which seems reasonable), this should be true for about one in every (1461)2 = 2,134,521 mother-baby pairs. So about 140 people in the U. S. should be born on February 29 and also have a mother born on that day.

I was actually reading the article expecting them to make some sort of mathematical mistake -- this feels like the sort of place where an "expert" is consulted and gives some ridiculous figure -- but they managed to restrain themselves.

melted-snowball said...

Or, I suppose, out of the 4 million births this year in the US, roughly 2500 will be to a mother born on 29 February, and the expected # of those which will be of a baby born on 29 February will be around 7.

Certainly, that's cool enough that if I were one of the 50 such mothers expected to give birth within + or -3 days of 29 February, I might want my doctor to induce...

PhilG said...

Is the article really saying that the baby is due on the 29th and they would induce on that day? The article is not clear, but it is standard practice to induce one or two weeks after the due date if baby has not taken its own initiative by then. It seems more likely that that is what they would plan unless there is a specific medical problem not mentioned, in which case there would only be a small chance of a 29th Feb birth date. Or am I being too naive not to think that they would induce on that day just to get some publicity?