(CBS) -- Infant mortality in the U.S. have been on the decline, after years of rates remaining stagnant.
A report issued on Wednesday by the Centers for Disease Control and Prevention showed that infant mortality rates declined 12 percent from 2005 through 2011. During the five years prior to those dates, rates had remained constant.
In 2000, the infant mortality rate was 6.91 deaths per 1,000 live births. In 2011, the number dropped to 6.05 deaths per 1,000 births.
The CDC pointed out that infant mortality is often a good indicator of the health of a country.
"We are seeing a slight narrowing in the gap, and that's very encouraging," author Dr. Marian F. MacDorman, a senior statistician at the National Center for Health Statistics, told the New York Times. "But the gap is still really big."
Rates for four out of the five leading causes of infant death went down. Congenital malformations went down 6 percent, and short gestation/low birth weight went down 9 percent. Sudden infant death syndrome (SIDS) and maternal complications declined 20 and 7 percent, respectively. Only unintentional injury fatalities rose during the time period. Together, the top five causes account for 56 percent of infant deaths in the U.S. in 2011.
In addition, infant mortality went down 16 percent for non-Hispanic black women and 12 percent for non-Hispanic white women.
Infant deaths declined 20 percent or more in Georgia, Louisiana, North Carolina, South Carolina and the District of Columbia, areas which traditionally have had high rates. D.C., which had a rate of 14.05 deaths per 1,000 in 2005, expanded a home-visit program from pregnant women living in poverty and increased other health programs targeted towards mothers and their babies. Their number dropped to 7.86 deaths per 1,000 births in 2010.
No states had a statistically significant increase in rates. In fact, states with the highest rates experienced some of the greatest declines. The state with the highest infant mortality rate, Mississippi, saw their rates go down 15 percent from 2005 to 2010.
Neonatal mortality rates (deaths under the age of 28 days) declined 11 percent, and postneonatal (deaths between the age of 28 days and 1 year) declined 14 percent as well.
MacDorman said one other reason rates may be declining is because doctors are actively preventing planned early deliveries through methods including a March of Dimes campaign called "Healthy Babies are Worth the Wait" and a Department of Health and Human Services program called "Strong Start." In addition, more hospitals banning mothers from scheduling births prior to 39 weeks of gestation without a medical reason.
"It's been going on for a few years now and I think it has had an impact," MacDorman said. "It's maybe leading to just a little change in the culture."
Dr. Vincent Bonagura, professor of pediatrics at the Alexandra and Steven Cohen Children's Medical Center of the North Shore-Long Island Jewish Health System, in Great Neck, N.Y., told HealthDay that care and diagnosis has improved greatly during those years.
"We know now if a baby will need surgery or medical therapy even before they are born," he said.
While Michael Fraser, chief executive of the Assn. of Maternal and Child Health Programs in D.C., said the results are good news, he explained to the Los Angeles Times that much needs to be done to maintain the decline. Looking at care beyond pregnancy needs attention.
"It is a critical time to celebrate success but also to figure out how we are going to keep this going," he said. "It would be horrible to see in five years for the rates to go back up because we are not able to sustain this level of intervention."
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