The nonprofit group said West Virginia had a preterm-birth rate of 14.4 percent in 2005.

That's compared to 12.7 percent nationally, a D grade.

No state earned an A.

Maternal smoking and lack of health insurance have been cited as the two largest contributors to preterm births.

The March of Dimes report says about a third of women of child-bearing age in West Virginia smoke.

About 23 percent of those women have no health insurance.