Christmas conceptions lead to autumn baby boom
More babies are conceived at Christmas in England and Wales than at any other time of the year.
Two decades of Office for National Statistics data found a surge in births around 40 weeks after the festive period.
While Christmas Day, Boxing Day and New Year's Day all had the lowest numbers of births.
Explanations include couples spending more time together or targeting the start of the new school year.
The ONS said: "A peak in births in late September shows that more babies are conceived in the weeks leading up to and days after Christmas than at any other time of the year."
All things being equal there would be 1,800 babies born every day.
But there is a clear autumn baby boom with 1,974 births on the most popular day - 26 September.
Explanations include parents trying to give their children an advantage by making sure they are born at the beginning of a school year.
Christmas Day, Boxing Day and New Year's Day are the least common days for giving birth each year.
This could partly be down to fewer scheduled births by Caesarean section taking place on those days.
Allan Pacey, a professor of andrology at the University of Sheffield, told the BBC: "The idea that more babies are conceived over the Christmas period makes a lot of sense.
"I'm sure the odd celebratory sherry has something to do with it too."