Robin Roberts returns to "Good Morning America"

Five months after undergoing a bone marrow transplant, Robin Roberts is back on television in the morning.

Roberts said Wednesday she'd been waiting 174 days "to say this, good morning America."

The morning-show host is recovering from MDS, a blood and bone marrow disease. She looked thin with close-cropped hair but was smiling broadly, back at work on "Good Morning America" at ABC's studio in New York City.

Roberts received a special message from President Barack Obama and first Lady Michelle Obama during Wednesday's show.

"Good morning America, and welcome back Robin!" Mr. Obama said in a video segment. The first lady said, "The whole Obama family, we have been thinking about you and praying for you."

"You are an inspiration to all of us!" the president added.

Roberts chronicled her treatment, regularly posting updates about her health condition. She previously battled breast cancer.

ABC announced Roberts will interview first lady Michelle Obama later this week, to be shown next Tuesday.

On Wednesday morning, #WelcomeBackRobin was trending on Twitter.