The U.S. fertility rate has dropped to an all-time low, according to new CDC data.

Researchers say it's not a blip.

It's a generation of women choosing to wait or not have children at all.

Our William Brigham has more.

That's right, Jeff.

This trend has been going on for a while.

Since 2007, the number of Americans having babies has dropped 23 percent,

and that means not enough kids are being born to replace older workers or those that die.

If this trend continues, or unless immigration levels change, the nation will have 8 million

fewer residents by 2050.

But there are some nuances to these numbers.

There was a 7% drop in teen pregnancies last year, which many experts say is a very good thing.

So for more on what this means for current and future generations, we are joined by Brian Mann of NPR.

He has been reporting a long investigative series about global population trends.

Brian, welcome back to the show.

The U.S. population has been on this significant downward trend for almost two decades.

You've spent a good deal of time looking into this. What does your reporting

say about what is driving this? You know, there's a mix of factors, William, that are

causing women and young couples to choose to have fewer children, smaller families, and in some

cases, no children at all. And as you say, this is already affecting the fabric of the country.

The population of the United States is aging rapidly.

The growth of the population has slowed dramatically already.

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