The couple announced the big news six weeks after welcoming their first child together, son Shai Aleksander, during a Tuesday appearance on Good Morning America.
"I am definitely a little bit nervous but I am very excited to get back," Murgatroyd, 30, noted when expressing concern about the type of shape she's in after giving birth. "I have definitely missed the dance floor. I haven't been able to defend my title with [Nyle DiMarco], so I want to get back out there."
Murgatroyd was referring to her Season 22 win with the deaf America's Next Top Model winner last year.
The new mom plans to ease into the drastic transition of raising a child at home to competing on a tense and stressful show like Dancing with the Stars.
"I just want to be healthy," she said. "I want my body -- It's going to take a little bit longer, I think, to get back up to the fitness I was doing and had before. I think it's going to be okay. I am going to take it slowly and hopefully I have an awesome partner to go through this with."
Murgatroyd and Chmerkovskiy have had a friendly rivalry in the competition over the years and plan to continue it.
"I'm not afraid [of Peta]. I don't know if everybody remembers the history, but last time we were together on the same season, I won," recalled the new dad, who took a break from Seasons 19 to 22. "I don't care how many [mirrorball trophies] she has. We'll see what happens."
The engaged couple hinted Shai will probably make an appearance in the ballroom at some point, and it's clear Murgatroyd and Chmerkovskiy are loving every minute of parenthood.
"It's definitely a special time. I was always wanting to have kids and never thought it would be like this. You can't just stop staring at this little person. This is the only difficult part about coming back on the show this time, because it will take time away from being with this dude," Chmerkovskiy said of his son.
The bad-boy of the ballroom jokingly added, "I just want to make [Peta] coming back and winning as difficult as possible."