"It was a bit shocking at first, but I got over that pretty quick," Trebunskaya, 32, tells PEOPLE of finding out she was expecting her first child.
"Even though this was not planned, I believe things happen for a reason and it was meant to be."
She continues, "I've always wanted to have a baby, but it was never the right time. I guess it was fate — or the universe — telling me it was time to be a mom."
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While she had hoped to return, once she realized she was expecting, it was no longer an option. "I don't think it would be best for my health and the baby's health to go through all of those hours of rehearsals," says Trebunskaya.
"I'll definitely be watching. They have been so supportive of me. They are still my family and I think they have a great cast this season. I think Valerie Harper and Jack Osbourne are going to be amazing. They have such phenomenal personal stories," she adds.
Now in her second trimester, Trebunskaya, who divorced former DWTS pro Jonathan Roberts last year, says she plans to make a few more appearances with Ballroom With a Twist through September, before taking it easy for the remainder of her pregnancy.