Feeling lucky? A new study shows you might need it if you're "googling" medical advice instead of asking your doctor.

In a study of 1,300 Google search results related to infant sleep safety, researchers found that only 43.5 percent of websites provided accurate information. The rest were either inaccurate or irrelevant.

"It is important for health care providers to realize the extent to which parents may turn to the Internet for information about infant sleep safety and then act on that advice, regardless of the reliability of the source," said Dr. Rachel Moon, the pediatrician who led the research effort published in the Journal of Pediatrics.

Moon, a Sudden Infant Death Syndrome researcher at the Children's National Medical Center in Washington, D.C., used 13 search phrases related to infant sleep safety, including "infant sleep position," and "pacifier infant" to conduct her study. Moon and her team analyzed the first 100 Google results for each phrase, and deemed them accurate if they matched up-to-date recommendations from the American Academy of Pediatrics.

Moon's colleague, Brandi Joyner, told ABCNews.com she regularly tells patients to double-check their online sources' validity before acting on the advice. Joyner is clinical research coordinator at Children's National Medical Center and health educator at the Children's National WIC clinic in Washington, D.C., where she tells women how to keep their children safe even at naptime and bedtime.

"If you want to turn to the Internet, make sure the website is ending in .gov or.org or .state," Joyner said.

The most accurate sites were from government organizations, which were accurate 80.1 percent of the time, according to the study. Researchers found that the least accurate websites were blogs, which were only accurate 30.9 percent of the time.

A physician in Los Angeles, Dr. Frisca Yan-Go, said many of her patients come into her office under the impression that they can sleep in the same bed as their infants, which may result in suffocation. In fact, since many of her patients are Chinese, and Chinese culture includes co-bedding with children, she has to ward off misinformation from the Web and from her patients' upbringing.

"It's good to have the Internet, but wrong information or bad information is worse than no information," she said.

This BabySleepSite.com and BabyCenter.com both say babies can sleep on their stomachs when they have the ability to roll onto their bellies without help. However, the American Academy of Pediatrics says only "Supervised, awake tummy time is recommended" for babies up to one-year-old and "Always place your baby on his or her back for every sleep time."

Dr. Ari Brown, a pediatrician based in Austin, Texas, said sometimes Internet research can be helpful. Her patients' parents research symptoms and look for signs in their children that they otherwise might not think to share with the doctor if they hadn't read a health blog or article or advertisement beforehand.

"The flip side is that most parents don't fact check," she said.

Brown said she once had a parent tell her, "I read online that I shouldn't use diaper wipes when my daughter pees – only when she poops."

This, of course, is untrue.

"People read all kinds of stuff online," she said, adding that it can sometimes cause a lot of anxiety. "But information can be very powerful when it's good information."

But infant sleep safety is just one subject area that has inaccurate Web information, doctors say.

What if a patient finds a bump and reads online that it's probably a cyst, asked Dr. Andrew Carroll, a family physician in Arizona. That patient might not see a doctor, and find out months down the line that the bump was melanoma all along.

Carroll said many of his patients also come to his office with bogus health products they read about online. One such patient showed him a bottle of Metanx, which is intended to help with diabetic nerve damage pain, and asked if there was anything less expensive that she could take instead.

"'You can take a normal multivitamin,'" Carroll said, upon looking at the ingredients. The product wouldn't have hurt her, but it wouldn't have particularly helped either, he said.

He said he's also had patients approach him about ASEA water, which he tells them basically amounts to saline (salt water) and doesn't have any real health benefits.

"People Google stuff all the time," Carroll said. "That's OK if it prompts someone to come into the office. What we're concerned about is when people find inaccurate information on the internet and something could be potentially dangerous."