A spokesman for Puerto Rico Gov. Ricardo Rossello did not immediately return a message for comment.
The study noted that mortality in Puerto Rico had been slowly decreasing since 2010, but spiked after the hurricane.
"The American people, including those grieving the loss of a loved one, deserve no less".
"The results of our epidemiological study suggest that, tragically, Hurricane Maria led to a large number of excess deaths throughout the island", Carlos Santos-Burgoa, the study's lead researcher, said in a statement. People from all social and economic backgrounds perished in the storm, though the death count was proportionately higher for Puerto Ricans in poorer communities and elderly men, according to the report.
"That caused a number of issues", Goldman said, explaining that people were forced to exert themselves physically or were exposed to intense heat without fans or air conditioning.
The report, which analyzed processes related to death certification, says that physicians and forensic physicians are among those in Puerto Rico who are authorized to complete death certificates, but that most physicians have no formal training in how to do so.
Puerto Rico said in a report to Congress earlier this month that it saw 1,427 more deaths "than normal" in the four months after Hurricanes Irma and Maria hit, though it said not all of the deaths may be attributable to the storms.
However many people also died as a result of poor healthcare provision and a lack of electricity and clean water.
In estimating the true death toll of Hurricane Maria, researchers looked at historical data to estimate how many people would have died had the storm not hit the island.
Power has not yet been fully restored to Puerto Rico almost a year after the hurricane, and outages remain common. That's nearly twice the government's previous estimate. "That's unusual in the US after a disaster".
Besides those directly killed by the storm, scores of others died when they weren't able to access hospitals over impassable roads, couldn't plug in dialysis machines when the island went dark or couldn't cope with the stress after the storm.
San Juan Mayor Carmen Yulin Cruz, who was vocal in her criticisms of the federal government's handling of relief efforts after the hurricane, said the deaths reported Tuesday were due partly to negligence.
Researchers said they took into account an 8 percent drop in Puerto Rico's population that occurred from September 2017 to mid-February 2018, when tens of thousands fled the damage left by the storm.
The latest study says that from the period ranging from September to December 2017 alone, there were an excess of 2,098 deaths, and 2,975 from September 2017 to February 2018.
In May a Harvard University-led research team estimated that 4,645 lives were lost from Maria on Puerto Rico.
Rossello pledged to carry out the recommendations, though there are questions about Puerto Rico's ability to do so.