More babies are born during the middle of the week than on the weekend, and this is regular vaginal births not caesarians, that doctors could schedule. Furthermore, it does not seem that doctors are delaying weekend births to Monday since Monday is not correspondingly too high.
2006 data from the Center for Disease Control is even more extreme than the 2000 numbers.
Why is this? I would expect that babies wouldn't know what day it was before they were born.
Turns out that the phase of the moon and the weather has no effect on birthrate.