Moms in the U.S. are increasingly breastfeeding their infants, but still not as long as experts want.

By the time U.S. babies are six months old, 22 percent of them are exclusively breastfed compared to 11 percent in 2007, according to the latest statistics from the Centers for Disease Control and Prevention released Monday.

CDC officials said they're pleased by the trend, but noted that large numbers of mothers stop breastfeeding earlier than the full year that is recommended by health experts.

Eighty-one percent of babies are ever breastfed now, up from 74 percent a decade ago. But just 31 percent of mothers are still breastfeeding their babies after their first year. That's better than just 21 percent in 2007, but still not the statistics the American Academy of Pediatrics is hoping to see.

"We are pleased by the large number of mothers who start out breastfeeding their infants," said Ruth Petersen, director of CDC's Division of Nutrition, Physical Activity, and Obesity. "Mothers can better achieve their breastfeeding goals with active support from their families, friends, communities, clinicians, healthcare leaders, employers, and policymakers."

Oregon moms breastfed the longest, with 45 percent breastfeeding their babies through one year of age. Mississippi was on the other end of the spectrum, as just 11 percent of women there breastfeed their babies the full year.

The CDC has set a goal of 81.9 percent of infants ever breastfed. Twenty-nine states including the District of Columbia met that goal.