Babies Are Booming in the U.S.

The fertility rate in the United States is now at its highest level since the end of the baby boom more than 35 years ago, a circumstance that makes the United States somewhat unusual among industrialized countries.

Little Sydney Degner, born 11:30 this morning, is part of a generation that doesn't even have a name yet. Like most kids her age -- in the United States, at least -- Sydney is not an only child. She is one small example of a population boom, that sets the United States apart.

Nearly 4.3 million children were born last year in the United States -- the largest number of births since 1961.

In 2005, there were two children born for every American woman. Last year, the so-called "fertility rate" rose to 2.1 children for every woman. That's still nowhere near what it was during the height of the baby boom, when the rate hovered somewhere between three and four kids per family.

But a fertility rate of 2.1 is what population economists call "replacement level," which, roughly speaking, means the number of child births balances with the number of parents.

In a recent USA Today story, fertility experts cited financial prosperity, immigration and job security for working moms as reasons behind the increase in births.

Over the past few decades, most of the industrialized world has struggled with declining fertility. In Italy, one child is now the norm, despite pleas from the pope and offers of financial incentives that include cash payments of more than $1,000 to every couple who has a second child.

In Russia, only one out of three women has kids. So Vladimir Putin recently offered even more money -- up to $10,000, to have more kids.

Here in the United States there are no such incentives, but families are having children anyway. Experts say birth rates have gone up significantly among the rich, who can afford to have more children.

The U.S. population topped 300 million last year and is expected to reach 400 million by 2040.