Snooki announced earlier this month that she is expecting a baby with her fiancé Jionni LaValle.
Magro has now told E! Online that she has become a "different Snooki".
"She's doing really good," he said. "She's not drinking. She's got her act together and I'm really happy for her."
Magro also urged people to stop making judgements about Snooki, saying: "The fact that she likes to have a good time has nothing to do with what kind of parent she's going to be. It's her life and whatever's going to make her happy at the end of the day, she has to realise that that's what she has to do."
Jersey Shore's Vinny Guadagnino has admitted that the news of Snooki's pregnancy was a "shock" but added that it is a "cool thing".
Meanwhile, Deena Cortese has said that the reality star will be a "great mum".
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