SEATTLE — Could a parent's marijuana use, even before their child is born, influence how their kids do drugs? According to a study just released from the University of Washington the answer to that question is: yes.

This recent study builds on research that started in the 80's. During that time, UW's Social Development Research Group started looking at fifth graders at several Seattle elementary schools then followed them through their 30's. 

They found people who used marijuana in their teen years tended to have lower academic and economic outcomes than those who used as adults or not at all.

Then in 2002, the group recruited those participants who had become parents and interviewed their children about alcohol and drugs beginning at the ages of six and 10 respectively. In all, they spoke with 360 children.

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What they found is that kids whose parents used marijuana as adolescents and teens were 2.5 times as likely to use marijuana and 1.8 times as likely to use alcohol compared to children of non-users. 

In addition, parents who admitted to chronic use, which is described as ongoing and frequent, had kids who were 4.5 times as likely to use marijuana and 2.75 times as likely to use alcohol. 

The science of why is still unclear and more studies are needed to uncover the relatively high usage in kids. 

The study's lead author, Dr. Marina Epstein, said the takeaway is that they've proven the history of marijuana use in parents is an important risk factor for kids.

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