For the second consecutive year, the United States earned a "D" for its high premature birth rate, according to a March of Dimes report card.

More than 540,000 babies are born prematurely in the U.S. each year, according to the March of Dimes, which pegs the cost of premature birth at $26 billion annually. Here's an excerpt from the organization's press release:

"Although we don't yet understand all the factors that contribute to premature birth, we do know some interventions that can help prevent it, and we must consistently make use of all of these," said Dr. Jennifer L. Howse, President of the March of Dimes.

She cited smoking cessation programs; health care before and during pregnancy; progesterone supplementation; and improved adherence to professional guidelines on fertility treatment and early Cesarean-sections and inductions.

The report card also gave each state a grade based on the number of premature births it recorded. Although seven states improved over the past year, no state earned an "A." Seventeen states, the District of Columbia and Puerto Rico all earned "F" grades.

How did your state do? What are some of the factors in your state that might contribute to the problem of premature births? How much do these births contribute to your state's health care costs? What are ways that your state could reduce the problem?

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