Robin Roberts said on "Good Morning America" that this Friday will be her last day on the air before she begins an extended medical leave.
Roberts, who said in June that she was diagnosed with the blood and bone-marrow disease myelodysplastic syndrome, or MDS, is preparing for a bone marrow transplant. She said she will check into the hospital next Tuesday, Sept. 4, to "begin the process."
"It still takes about ten days after being admitted because there's some things that you have to go through before the transplant actually occurs," she said.
Katie Couric, the women of "The View," and Diane Sawyer are all expected to contribute to "GMA" during her leave.
Roberts, 51, said as she went on a previously scheduled vacation Aug. 1 that she was "not feeling well" and would "get some vacay." Five years ago, she successfully battled breast cancer.
Beginning on Thursday, her doctors will post information on her recovery. They will also direct viewers to BeTheMatch.org for information on how to become a bone marrow donor.
In Roberts' case, she said, her sister turned out to be "a perfect match."
She also posted a picture of her dog on Monday, saying he will have to stay elsewhere while she recovers because of her weakened immune system.
Watch the announcement: