The March of Dimes estimated that, since 2006, about 176,000 fewer babies have been born too soon because of improvement in the preterm birth rate, potentially saving about $9 billion in health and societal costs.

"Although we have made great progress in reducing our nation's preterm birth rate from historic highs, the US still has the highest rate of preterm birth of any industrialized country. We must continue to invest in preterm birth prevention because every baby deserves a healthy start in life," said March of Dimes President Dr. Jennifer L. Howse. "A premature birth costs businesses about 12 times as much as uncomplicated healthy birth. As a result, premature birth is a major driver of health insurance costs not only for employers.

The national preterm birth rate peaked in 2006 at 12.8 percent after rising steadily for more than two decades, according to the National Center for Health Statistics. The 2012 rate is a 10 percent improvement since the 2006 peak and the best rate since 1998. When compared to 2006, almost all states had lower preterm birth rates in 2012.

Disparities Gap Slowly Narrowing

The 2012 preterm birth rate among non-Hispanic black infants remains the highest of all the racial groups at 16.5 percent, down from 18.5 percent in 2006 and the lowest in more than 20 years. The gap between blacks and whites has been slowly narrowing, but the preterm birth rate among non-Hispanic blacks is still more than 1.5 times the rate of non-Hispanic whites.

Preterm birth (before 37 weeks of pregnancy,) is a serious health crisis that costs the US more than $26 billion annually, according to the Institute of Medicine. It is the leading cause of newborn death, and babies who survive an early birth often face the risk of serious and sometimes lifelong health problems, such as breathing problems, jaundice, developmental delays, vision loss and cerebral palsy. Babies born just a few weeks too soon have higher rates of death and disability than full-term babies. Even infants born at 37-38 weeks of pregnancy have an increased risk for health problems compared to infants born at 39 weeks.

On the 2013 Report Card, 31 states, the District of Columbia, and Puerto Rico saw improvement in their preterm birth rates between 2011 and 2012, earning seven -- Alaska, California, District of Columbia, Georgia, Indiana, Kentucky and New Jersey -- better grades. Nineteen states earned a "B," 17 states and the District of Columbia received a "C," five states got a "D," and only three states and Puerto Rico received an "F" on the report card.

California's success in achieving the March of Dimes goal is noteworthy. Not only is California home to half a million births each year, the most of any state, it also has a racially diverse population in a mix of urban, suburban and rural communities that have a variety of healthcare and economic needs.

The March of Dimes Report Card compares each state's preterm birth rate to the March of Dimes goal of 9.6 percent of all live births by 2020. The Report Card information for the U.S. and states are available online at: marchofdimes.com/reportcard.

The Report Card also gauges states' progress toward lowering their preterm birth rates by tracking contributing factors.

• 37 states, the District of Columbia and Puerto Rico reduced the percentage of uninsured women of childbearing age;
• 35 states and the District of Columbia reduced the percentage of women of childbearing age who smoke;
• 28 states the District of Columbia and Puerto Rico lowered the late preterm birth rate, infants born between 34 and 36 weeks gestation.