Maryland’s infant mortality rate, which has remained stubbornly high despite the state’s wealth, fell last year to its lowest level on record.

Gov. Martin O’Malley (D) on Wednesday touted the latest decline — from 7.2 deaths per 1,000 live births in 2009 to 6.7 per 1,000 last year — at a news conference in Baltimore.

“It’s not by chance but by choice that we are here today to celebrate a milestone,” said O’Malley, surrounded by other elected officials, health and social workers and an alternately cooing and crying baby. The governor acknowledged that more work remains to be done.

While the new figure is the lowest since recording began in the 1940s, it is still likely to hoover above the national average once 2010 figures become available. In 2009, the national average was 6.4 deaths per 1,000 births, and that number has generally been trending downward since the 1980s.

O’Malley has sought to make the issue a priority in Maryland, which chose to release its figure early to highlight continued progress.

O’Malley and other officials attributed two consecutive years of declines to better efforts to connect people with existing programs that provide prenatal and infant care and warn of the risks of putting a baby to sleep on its stomach.

Baltimore Mayor Stephanie Rawlings-Blake (D) recounted for the crowd advice she had conveyed to an old college friend once she learned that the new mother was putting her infant to bed that way because the baby fell asleep sooner.

“You could be a little groggy in the morning, or you could be at a funeral,” the mayor said she told her friend.

The statewide decline in infant mortality, officials said, was driven in large part by declines in Baltimore and Montgomery County. In Montgomery, the state’s largest jurisdiction, the rate fell from 5.5 deaths per 1,000 in 2009 to 4.3 per 1,000 last year.

The latest numbers also showed significant disparities remain based on race and socioeconomic status.

Statewide, the infant mortality rate remained steady for white babies at 4.1 deaths per 1,000. For black infants, it fell from 13.6 deaths per 1,000 in 2009 to 11.8 deaths per 1,000 last year.

Prince George’s County and Baltimore, Maryland’s two largest majority-black jurisdictions, had among the highest rates in the state.

Prince George’s rate was 9 deaths per 1,000 births, a slight increase over 2009, when it was 8.7 deaths per 1,000 births. The county’s longer-term trend has been downward, however.

Baltimore saw its rate drop from 13.5 deaths per 1,000 in 2009 to 11 deaths per 1,000 last year.

Two Eastern Shore counties also recorded notably high rates last year: Worcester, with 16.7 deaths per 1,000 births; and Queen Anne’s, with 10.3 per 1,000. Given the relatively small populations in those counties, a small number of deaths can significantly increase the rate, however.

Lt. Gov. Anthony G. Brown (D), who has played a role crafting Maryland’s health policies, noted the ups and downs on a graph showing the infant mortality rate in recent years but said it showed clear progress.

“It may not be the smoothest glide path, but we’re moving in the right direction,” he said.