By Stephanie Stahl

PHILADELPHIA (CBS) – About 90 percent of pregnant women in the United States take at least one medication, but how safe is that? A new government report says there’s a lot of confusion and conflicting information online. 3 On Your Side Health Reporter Stephanie Stahl has the details.

The Food and Drug Administration estimates medicines taken during pregnancy cause about 10 percent of birth defects. And this new research shows pregnant women can’t always rely on information they find online.

Bianca Holmes suffers from allergies, and needs medicine to help her through her worst days. But she’s pregnant, and doesn’t want what helps her to hurt her baby, so she goes online for guidance.

“The confusing and contradictory information leaves me kind of scared,” said Bianca. She’s smart to be scared. A government study found women are being misled by information on multiple websites.

“We found 25 active Internet web sites that post such lists of safe medicines to take during pregnancy. Few of those medications that were on those lists actually had data to back up their claims for safety,” Cheryl Broussard, with the CDC National Center on Birth Defects and Developmental Disabilities.

In one study of 245 products with 103 components that were listed as safe on various sites. In 42 percent of the cases, researchers were unable to determine the risk to the unborn child.

“While we wish we knew the effect of certain medications on pregnant women, we really aren’t able to do studies where we give half the women a certain medication and half the women a different medication to assess the safety,” said Dr. Siobhan Dolan, a Medical Advisor to the March of Dimes.

The March of Dimes points out the confusion is compounded by the fact that certain drugs are safe only during certain times of the pregnancy.

“Everything that goes into me, it also affects the baby,” said Bianca. That’s why experts say it’s critically important for pregnant women to talk to their doctors before taking any medication.

If you want to research or check some drugs online, both the CDC and the March of Dimes suggest using the website

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