ATLANTA -- Federal health officials said on Thursday that infant mortality had declined more than 45 percent in the United States since 1980, but the good news was overshadowed by data showing black newborns were now even more likely to die in their first year than white babies.

A study by the Centers for Disease Control and Prevention revealed that there were 14 deaths per 1,000 live births among blacks in 2000, almost two-and-a-half times the 5.9 deaths per 1,000 live births reported for whites the same year.

In comparison, infant mortality for blacks was only double that of whites in 1980, when there were 10.9 deaths per 1,000 live birth.

Infant mortality rate declined to 6.9 deaths per 1,000 live births in 2000 from 12.6 deaths per 1,000 live births in 1980.

The CDC attributed the widening racial gap in infant mortality in part to the higher tendency for black infants to be born with a low birthweight, under 5.5lbs (2.5kg), or a very low birthweight, under 3.3lbs (1.5kg).

"There is still a persistence of a twofold risk of low birthweight among black babies compared to white babies, and there is a three-fold risk of very low birthweight among black babies compared to white babies," Reuters quoted Dr. Wanda Barfield, an epidemiologist in the CDC's Division of Reproductive Health, as saying.

Barfield added that the risk of death associated with low and very low birthweights had decreased more among whites than blacks in the 1990s.

Smoking, stress, certain infections and lack of access to pre-natal medical care are factors believed to increase the likelihood that an expectant mother will deliver a baby with a low birthweight.

The CDC, which hopes to reduce infant mortality to 4.5 per 1,000 live births among all racial groups by 2010, said its study indicated that more research was needed to develop strategies aimed at preventing premature deliveries, especially in the black community.

A study in the June, 2002 issue of **** Pediatrics **** indicated that the United States might be able to cut its infant mortality rate if it allocated more medical resources to prenatal care than to intensive newborn care.

The study's researchers showed that low-birthweight newborns in the United States died at rates similar to those in Canada, Australia and Britain, which all devote more of their medical resources to prenatal care than intensive newborn care.