A study published in the American Journal of Clinical Nutrition said pregnant women may be able to eat more fish than previously thought thanks to what appear to be minimal negative effects from mercury consumption on their unborn children, but experts say sushi is a whole different story.

The U.S. Food and Drug Administration recommends that women eat no more than 12 ounces of fish or two fish meals a week, but Myers said it's considering whether to allow more.

For now, Dr. Jeff Ecker, who chairs the American College of Obstetricians and Gynecologists' Committee on Obstetric Practice, said women should continue to follow the current FDA recommendations. He said the study might help convince the FDA to change the guidelines, but more research analysis is needed.

"The study suggests, as has been known for a while, that there are real benefits from fish eating," he said. "The balance between the benefits and potential risk of mercury exposure and this work suggest that there's not as direct a relationship between mercury exposure and adverse outcome as initially thought."

Still, pregnant women are told not to eat raw or under-cooked fish for several reasons, said teratologist Robert Felix, who studies and counsels women on how things during pregnancy effect their unborn children. If it is not prepared and handled properly, sushi can cause parasitic infections, be cross-contaminated by bacteria or other substances or contain high levels of mercury, Felix said.

The U.S. Centers for Disease Control and Prevention recommend that pregnant women only eat fish cooked to at least 145 degrees Fahrenheit.