Polizzi confirmed earlier this week that she is engaged to boyfriend Jionni LaValle and expecting his baby.
Addressing his co-star's big news, Guadagnino defended the 24-year-old from accusations that she is too "irresponsible" to become a mother and said that the Jersey Shore cast would continue to give support.
"I think she'll work on it," he told The Huffington Post. "Any mum, whether they're 40 or 24, doesn't know what it is like until the baby is there.
"Everyone can talk about how irresponsible she is and how she drinks, but you don't know how she'll be when the baby comes out.
"We all get into our hardships with each other and petty arguments but this is real life. She is pregnant and we are there for each other...I think it is a cool thing. It was definitely a shock, but you have to adapt to whatever life throws at you."
Guadagnino, who famously slept with Polizzi during a rough patch in her relationship with LaValle, also expressed confidence in the father-to-be's ability.
"I don't know the kid, but it is going to be a life-changer for him," he said. "But they have good families so they have people to help them."
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