One out of eight babies is born prematurely in the U.S., which amounts to about 540,000 preterm births each year. Preterm birth is the leading cause of death for newborns, and costs the country around $26 billion per year. A new report card examining the issue gave the whole country a grade of “D,” and few states fared better.

While the nationwide rate of premature births was only 11.4% in 1997, it increased to 12.7% in 2005, 12.8% in 2006, and 12.7% in 2007, the most recent three years on which data is reported.

The criteria used in the report assign a grade of “A” for states in which preterm births are 7.6% or less of all live births. No state earned that grade, with Vermont the only state to even earn a grade of “B” at 9%. Seventeen states earned a grade of “F,” with Mississippi coming last at 18.3% (Puerto Rico had a prematurity rate of 19.4%).

A baby born before 37 weeks of gestation is considered premature. Typically, it is too small and too sick to go home, and has to spend weeks or months in the NICU (Neonatal Intensive Care Unit). Eventually, most preemies go home, but they often face the risk of death and severe complications in their lifetimes, including breathing problems, cerebral palsy, mental retardation and learning problems, chronic lung disease, and vision and hearing problems.

The only piece of good news from the report was that several states have made progress in implementing measures that can prevent premature births. These include smoking cessation programs, pre-natal care, progesterone supplementation, and improved adherence to professional guidelines on fertility treatment, early C-sections and inductions. For example, 33 states reduced the percentage of women of childbearing age who smoke and 21 states reduced the percent of uninsured women of childbearing age (uninsured women typically have less access to prenatal care).