President Trump's warning to pregnant women this week to stop taking Tylenol, based on his

unproven claim that it can lead to autism, sparked widespread concern and many questions

about what the science actually shows. So we're going to try to take some time and answer

some of those questions. Let's start with Tylenol, which doctors have turned to as the best

option for treating pain and fever during pregnancy.

On Monday, President Trump blamed acetaminophen in part for a significant rise in the number of cases of autism.

Here's what he said.

Acetaminophen, which is basically commonly known as Tylenol during pregnancy can be associated with a very increased risk of autism.

I want to say it like it is. Don't take Tylenol. Don't take it. If you just can't, I mean, it's a fight like hell not to take it,

there may be a point where you have to and that you'll, you have to work out with yourself.

For more on this, we're joined first by Dr. Linda Eckert.

She's an author and a professor of obstetrics and gynecology at the University of Washington.

Dr. Eckert, welcome to the News Hour. Thanks for joining us. Well, thank you. So scientists have been looking at this link

between acetaminophen and autism for decades. In the announcement, we should point out that

the White House leaned very heavily on the research of the dean of Harvard School of Public Health, Dr. Andrea Baccarelli, quoting him as saying there is a causal relationship between Tylenol and autism. Just tell us what does most of the research on this issue show?

Most of the research does not bear out that there's a causal relationship.

Causal relationships are quite hard to prove, actually.

And the research on Tylenol has been quite reassuring overall.

And there was actually many studies, several great studies, that have looked at this.

And the most recent one, that is a very powerful study was done

in Sweden where they looked over 250,000 individuals and they also were able to look at siblings

where people had environmental and sibling relationships genetics in common.

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