"There are far fewer Yazidi refugees on Mount Sinjar than previously feared and they are in better condition than previously believed," Xinhua quoted Defence Department spokesman John Kirby as saying.
Kirby noted that the refugees continue to have access to the food and water that the US troops have dropped.
On Wednesday, a team of less than 20 US personnel conducted an assessment of the situation on Mount Sinjar and the impact of US military actions to date, Kirby said.
The team did not engage in combat operations and all personnel have returned safely by military air to Erbil, the capital of Iraq's autonomous Kurdish region, the spokesman said.
The White House said earlier on Wednesday that the establishment of humanitarian corridors and airlifts are among options being considered by President Barack Obama to evacuate the Iraqi civilians trapped by the Islamic militants on the mountain.