Updated at 5:20 p.m.
The March of Dimes has released its annual state rankings of premature birth rates, giving Missouri a grade of "C" for the second year in a row.
The state's preterm birth rate has been gradually improving over the past five years, falling from 12.8 percent in 2006 to 11.6 percent in 2011. That puts Missouri right about at the national average, and just slightly better than neighboring Illinois.
Cardinal Glennon neonatologist Dr. Bill Keenan says many factors can contribute to a baby being born three or more weeks before its due date.
"One of the increasing risk factors in the United States in particular is maternal obesity," Keenan said. "As women have gained weight, the incidence of prematurity has gone up, and the risk of complicated deliveries has gone up."
Other risk factors include maternal smoking, and lack of access to prenatal health care.
The Director of Newborn Medicine at St. Louis Children's Hospital, Dr. F. Sessions Cole, calls preterm birth a major problem for our region.
Cole says babies born too soon can have serious problems with their lungs, liver, or kidneys. They can have trouble defending themselves against infection. And he says their brains may not be ready for life outside the womb.
“Even though they may not develop acute brain problems within the first month after birth, sometimes these babies can encounter problems with learning, with coordination, with speech and language that may not be noted until they get into kindergarten,” Cole said.
Cole says mothers who are able to carry their babies to term should always do so.
According to the U.S. Centers for Disease Control and Prevention, complications from premature birth are the leading cause of infant death in the United States.
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