Winter appears to be a good time to make a baby: December is the most common month for conception in the United States and the United Kingdom.
No one knows why. Some have suggested sperm could be healthier in cold weather.
According to a 2006 chart compiled by economist Amitabh Chandra of Harvard University, using U.S. data for each date from 1973 through 1999, the largest number of births occur in September.
The most popular birthday? Sept. 16.
-- Judy Peres
ActiveStyle on 01/26/2015