Today's kids are getting their periods earlier than previous generations.

The trends that we're seeing are a bit concerning since it's really heavily connected to later life health conditions.

It's Tuesday, July 2nd, and of course today is Science Friday.

I'm Cyfry producer Kathleen Davis. Today is Science Friday.

I'm Cyfry producer Kathleen Davis.

It's been a noted trend in recent years

that kids aren't just getting their periods earlier.

Those periods are less regular than in years past too.

A new study finds these differences are most noticeable for kids who are low income and not white.

There's an urgency to find out why this is, because these can be a sign of future health issues into adulthood.

Guest host Anna Rothschild speaks with lead author Z. Van Wong about the study.

Welcome to Science Friday.

Hi, thank you for having me.

So let's start with your findings from this study.

Can you just explain what you found?

Yeah, sure.

So we looked at individuals within the U.S. who were born between 1950 to 2005,

and we found that younger generations tend to start their first period or what we call

Manarchy at a younger age so on average that's from like 12.5 years old for those who were born in the 1950s all the

way down to 11.9 years old among those who were born around 2005. And we also saw that the rate of early monarchy, which is defined

as first period before 11 years old, has also doubled over the years from 9% to about 16%.

One other thing that we did found very interesting is another marker for

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