Secretary of State Hillary Rodham Clinton has been admitted to a New York hospital for a blood clot stemming from a concussion she suffered earlier this month.
According to the Associated Press, Clinton's spokesman Philippe Reines said her doctors found the clot during a follow-up exam Sunday. She is being treated with anti-coagulants and was admitted to New York-Presbyterian Hospital in order for doctors to monitor the medication over the next 48 hours.
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NBC News reported that in his statement, Reines said: "Her doctors will continue to assess her condition, including other issues associated with her concussion. They will determine if any further action is required."
Doctors told NBC that the clot likely started in Clinton's legs and could be dangerous if it breaks free and lodges in the heart or lungs.
Dr. Cam Patterson, a professor and chief of cardiology at the University of North Carolina-Chapel Hill did not treat Clinton personally but said that the clot most likely developed after extended bed rest following her concussion.
Patterson told USA Today that deep vein thrombosis, or DVTs, can form when blood flow to the legs is reduced, such as on bedrest.
"When you're not moving around, you don't have as much circulation in your lower extremities, and the blood sits around in your legs longer than usual," Patterson said. "That just makes it more likely that it's going to clot. If blood is moving around rapidly because someone is active, that's less likely."
The signs of blood clots in the legs are usually swelling, redness and pain but according to the Mayo Clinic about half of all DVTs have no noticible symptoms.
According to the Wall Street Journal, Clinton was expected to return to work at the State Department this week but it is unclear if the latest health scare will keep her at home even longer. Officials at the State Department ruled out any foreign travel for the Secretary until at least mid-January.
(UPDATE, Dec. 31, 5:35pm)
Late Monday, Clinton's doctors released more information about the nature of her blood clot, revealing that it is "a clot in the vein that is situated in the space between the brain and the skull behind the right ear," CNN reported.
The doctors said it did not result in a stroke or neurological damage, and added they were confident that she would make a full recovery, CNN reported.
The doctors said Clinton will be released once the medication dose of blood thinners has been established, CNN reported.