I didn't expect it -- I used to have to take three bars to sleep. But last night I woke up at 4 am, put on sweatpants and an army jacket, and walked eight blocks to this deli that makes submarine sandwiches and got one, along with two Cokes, a Nantucket Nectars lemonade and two bags of chips.
Now, according to data from 2011, those born alive at 27 weeks have an 87 per cent chance of surviving, at 28 weeks it is 92 per cent and at 29 weeks, 95 per cent. It means that doctors are working on tinier babies, typically with more complications, than ever before.
This figure shows the percent difference between first babies and others for weeks 34 through 46: The general pattern is that first babies are more likely to be early (37 weeks or less), less likely to be on time (38-40), and more likely to be late (41 or more). In terms of relative risk, first babies are 8% more likely to be born early and 66% more likely to be late. And those differences are statistically significant (using a chi-square test, p < 0.001).