COLUMBUS, Ohio (AP)--Doctors are sending a warning to new mothers who feed their babies with breast milk purchased online.

A study by researchers at Nationwide Children's Hospital and Ohio State University says testing shows the breast milk can contain potentially dangerous bacteria including salmonella.

Researchers bought and tested more than 100 breast milk samples sold by women on one popular site, and 75 percent of those samples contained high amounts of bacteria that could sicken babies. Researchers did not identify the website.

The research also cites several cases in which babies got sick from a stranger's breast milk.

Breast milk also is provided through milk banks, whose clients include hospitals. But they screen donors and pasteurize donated milk to kill any germs.

Both online breast milk sites and milk banks charge fees.

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