The 37-year-old American dancer and 30-year-old Australian dance pro announced on Tuesday's episode of Good Morning America that they will compete on Season 24 after welcoming son Shai in January.
"I'm definitely a little bit nervous, but I'm very excited to get back," Murgatroyd said. "I definitely missed the dance floor and I haven't been able to defend my title with Nyle [DiMarco], so I want to get back out there."
"I just want to be healthy," she shared. "It's going to take a little bit longer, I think, to get back up to the fitness that I was doing and had before, but I think it's going to be okay. I'm going to take it slowly and hopefully I have an awesome partner to go through this with."
Murgatroyd won Season 22 with DiMarco before sitting out Season 23 due to her pregnancy. She gave birth to Shai on Jan. 4 after announcing in June that she and Chmerkovskiy were expecting.
"It's a definitely special time. I was always wanting to have kids and never thought it'd be like this. You just can't stop staring at this little person," Chmerkovskiy said. "I'm just enjoying [parenthood]."
"The only difficult part about coming back on the show this time [is] it'll just take time away from being with this dude," he added of his son before joking, "I just want to make [Peta] coming back and winning as difficult as possible."
The Dancing with the Stars pros introduced Shai to fans on Friday's episode of Good Morning America. Murgatroyd explained how they chose their son's name in a post on her All Things Fam and Glam blog the same day.
"We knew that we wanted a shorter name that wasn't super-complicated because 'Chmerkovskiy' is kind of a mouthful and he'll always have to spell it out for people. We finally settled on Shai, pronounced 'shy' and means 'gift' in Hebrew," the star shared.
"Shai's middle name, Aleksander, was all Maks. Maks didn't grow up with a middle name, but I definitely wanted Shai to have one. So we gave him his middle name after Maks' dad Aleksandr (spelled a little differently to honor Shai's heritage but also make it unique to him)," she said.
Dancing with the Stars Season 24 will premiere Mar. 20 on ABC.