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By Anthony Cave November 3, 2016

Anti-recreational marijuana ad cherry-picks data for claim on newborn babies and pot

The last-minute contributions opposing an initiative that would legalize recreational marijuana in Arizona continue to pile up, with even Las Vegas billionaire Sheldon Adelson shelling out $500,000 against the cause.

Much like the money, the ads against recreational marijuana continue to flow as well.

An Oct. 11 ad from Arizonans for Responsible Drug Policy, an anti-pot group, uses testimonies from two former Colorado politicians in highlighting the supposed dangers of recreational marijuana.

"In one Colorado hospital, 50 percent of newborns tested had marijuana in their system," former Denver Mayor Wellington Webb says.

This claim stood out to us right away. Could half of all newborn babies tested at this particular hospital really have marijuana in their system?

Deceptive data

The ad cites a September 2016 report from the Rocky Mountain High Intensity Drug Trafficking Area -- an interagency group focused on combating drug trafficking.

According to the report, "nearly half" of newborns tested in March 2016 at St. Mary-Corwin Medical Center in Pueblo, Colo., tested positive for marijuana.

Ciara Archer, a spokeswoman for the anti-pot group, also pointed us to a July 2016 CBS Denver story on the hospital. The article notes that the head of the neonatal unit, Dr. Steve Simerville, is reporting a "dramatic increase" in newborns with marijuana in their system.

We reached out to the hospital and dug into the numbers.

Colorado legalized recreational marijuana in 2012, but St. Mary-Corwin spokeswoman Wendi Dammann said babies have been drug tested at the hospital for at least a decade.

"The screening criteria was developed by both local hospitals (St. Mary-Corwin and Parkview) and Children’s Hospital Colorado," she said.

As far as the numbers cited in the ad, Dammann confirmed that five out of the 11 newborn babies tested in March 2016 did test positive for marijuana.

So that’s less than 46 percent -- not half -- of a handful of births in one month.

Cherry-picking one month of data makes the number of newborns who test positive for marijuana seem higher than it actually is. That is not the case.

From January 2016 through September 2016, 403 babies were born at St. Mary-Corwin. About one-quarter of those, or 101, were tested for marijuana.

Of those 101 newborns, 27 tested positive for marijuana in their systems. That’s a rate slightly under 27 percent.

And in 2015, the hospital saw 519 births. Of the 93 newborn babies tested for marijuana, 31 came up positive for marijuana. That’s a rate of 33 percent.

Marijuana use during and after pregnancy can be quite harmful. According to the National Institute on Drug Abuse, exposure to THC "could have profound and long-lasting consequences" to a baby’s brain and behavior, including neurological development.  

We wanted to know how these statistics compared to the country or states where marijuana is not legal, but we could not find much research on that point.  

However, Dr. Edith Allen of Phoenix Children’s Hospital, studied drug habits for pregnant women with criteria including personal or family history of drug use at St. Joseph’s Hospital and Medical Center between 2006 and 2010.

Her study found THC in 431 babies out of 727 mother-baby pairings tested -- almost 60 percent.

However, Allen pointed out that not every pregnant woman was tested.

Our ruling

The ad claimed, "In one Colorado hospital, 50 percent of newborns tested had marijuana in their system."

That hospital -- St. Mary-Corwin Medical Center -- did have more than 45 percent of their newborn babies tested test positive for marijuana in their systems.

The big issue with the talking point is it cherry-picks one month of data. Overall, from January 2015 through September 2016, almost 1 in 3 newborn babies tested for marijuana at St. Mary-Corwin came up positive for marijuana in their systems.

That’s not half, but it’s still pretty high. We rate the ad’s claim Half True.

Our Sources

ABC15, "Las Vegas mogul Sheldon Adelson is the latest big name contributor to anti-pot effort," Oct. 25, 2016

Political TV Ad Archive, "Mistake," Oct. 11, 2016

Rocky Mountain High Intensity Drug Trafficking Area, "The legalization of marijuana in Colorado," accessed Oct. 27, 2016

CBS Denver, "Hospitals reporting more babies being born THC-positive," July 11, 2016

National Institute on Drug Abuse, "Can marijuana use during and after pregnancy harm the baby?" accessed Oct. 31, 2016

American Academy of Pediatrics, "THC and concomitant illicit drug consumption during pregnancy," accessed Nov. 2, 2016 

Interview with Arizonans for Responsible Drug Policy spokeswoman Ciara Archer, Oct. 26, 2016

Interview with St. Mary-Corwin Medical Center spokeswoman Wendi Dammann, Oct. 26-27, 2016

Interview with Phoenix Children’s Hospital Dr. Edith Allen, Nov. 2, 2016

Browse the Truth-O-Meter

More by Anthony Cave

Anti-recreational marijuana ad cherry-picks data for claim on newborn babies and pot

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