WEDNESDAY, Nov. 12 (HealthDay News) -- When it comes to premature birth rates, the United States rates a "D," and 18 states plus Puerto Rico and the District of Columbia get failing grades.

That's the sobering conclusion of the March of Dimes' first annual Premature Birth Report Card, released Wednesday. Not a single state earned an "A." Only one -- Vermont -- received a "B," and 23 states were given a "D."

The report card was released on the sixth annual Prematurity Awareness Day, which is meant to draw attention to premature birth, which affects more than 530,000 babies each year in the United States. Premature birth (before 37 weeks' gestation) is the leading cause of newborn deaths and a major cause of lifelong ills such as cerebral palsy, blindness, hearing loss, learning disabilities, asthma and other chronic conditions.

"It is unacceptable that our nation is failing so many preterm babies. We are determined to find and implement solutions to prevent preterm birth, based on research, best clinical practices, and improved education for moms," March of Dimes President Dr. Jennifer L. Howse said in a news release from the nonprofit organization.

The group urged people to sign the 2008 Petition for Preemies, to send a message to federal and state lawmakers to take action on the issue.

For the report card, the March of Dimes compared actual preterm birth rates to the national Healthy People 2010 objective of lowering the preterm birth rate to 7.6 percent of all live births. The U.S. preterm birth rate was 12.7 percent in 2005, the most recent year for which statistics are available.

Since 1990, the preterm birth rate in the United States has risen about 20 percent, and preterm births cost the nation more than $26 billion a year, according to a 2006 Institute of Medicine report.

In addition to state rankings, the report card also analyzed several factors that contribute to preterm birth -- including smoking and uninsured women of childbearing age -- and prevention measures.

The report calls for:

• Increased federal support for prematurity-related research to learn more about the causes of premature birth and to develop strategies for prevention, along with improved care and outcomes for preterm infants.
• Voluntary reviews by hospital leaders of all Caesarean-section births and inductions of labor that occur before 39 weeks' gestation, in an effort to reverse the nation's rising preterm birth rate. The review should ensure that all C-sections and inductions meet established professional guidelines.
• Policymakers to improve access to health coverage for women of childbearing age and to support smoking-cessation programs as part of maternity care.
• Businesses to create workplaces that support mother and infant health, such as providing private areas to pump breast milk, access to flextime, and information on how to have a healthy pregnancy and childbirth.