New York - Nearly half of U.S. moms gain too much weight during pregnancy, according to a government study released Thursday.

Putting on too many extra pounds during pregnancy can harm the mom, and may cause a range of problems for the child, experts say.

The study found only about a third of women gain the recommended amount of weight, and about a fifth gained too little.

Overweight and obese women most commonly exceeded the guidelines.... Read More: VIN