New USC study looks at effect fluoride exposure may have in pregnant women

After two pregnancy losses, new mom Charlene Zamora wanted to do her best when she was carrying her now 7-month-old Levi.

"I was trying to stick to a really healthy diet trying to get, you know, regular exercise, anything they said like avoid during pregnancy, I would try to avoid," she said.

Now, a new USC study found that kids whose mothers had higher urine levels of fluoride in their third trimester had a higher risk of having neurodevelopmental problems at 3 years old.

Dr. Howard Hu, the chair of USC's Department of Population and Public Health, and his colleagues followed about 230 predominantly low-income pregnant Latina women living in Los Angeles for the study.

"The higher the fluoride exposures, the worse were the neurobehavioral scores on things that reflect things like anxiety, depression," Hu said.

The study adds to previous research suggesting that fluoride may harm fetal neurodevelopment. adding more fuel to the fluoride debate.

"One possible recommendation they could make, well maybe pregnant women should avoid drinking fluoridated water," Hu said.

Dr. Michael Fassett is a maternal-fetal medicine specialist at Kaiser Permanente West Los Angeles.

"There are all kinds of exposures and pre-existing conditions and things with pregnancy that can that have similar degrees of effect in terms of affecting these neurobehavioral outcomes," Fassett said.

Fassett says as of now, no major medical group or federal agency recommends women limit drinking fluoridated water during pregnancy.

"I think any steps away from either taking fluoride out of the water at this point or not using fluoridated toothpaste - I think it's very premature," Fassett said.

New mom Zamora says she tends to drink bottled water anyway, but says pregnant women should always discuss their concerns with their doctors.

"They're always the best resource for any patient that is going through pregnancy," she said.

The World Health Organization recommends a limit of 1.5 milligrams per liter of fluoride in drinking water to prevent tooth decay and says there's no evidence to suggest it needs to be revised.