CBNNews.com - There have been a record number of babies born in the U.S., according to a new federal report.

There were a little more than 4.3 million births in 2007, topping a baby boom record first set back in 1957.

But while the numbers show the U.S. is re-populating itself there is also a down side.

Unwed mothers account for 40 percent of the births and the teen birth rate was up for a second year in a row.

One researcher says the reason is because it is perhaps more acceptable today.