Tom Arnold is finally going to be a dad at 53 as his wife Ashley Groussman is confirmed pregnant with their first child. "We're really happy. I didn't think it was in the cards for me, I'll be honest, and so I was completely shocked," he tells PEOPLE. "It's a miracle."

He opens up about his fertility issue, "I have a very low sperm count." The former husband of Roseanne Barr elaborates, "It is hard on the women. I've tried with other people, but since there is a God we were unable to conceive. Now God said, 'This is it!' "

Tom and Ashley got married in 2009. It was his fourth marriage. They underwent a series of in vitro to have a child, and were thrilled to find out that it worked. She's already seven months along now. "Yesterday she had an ultrasound and she keeps sending them to me and she's like, 'You can see he's sucking his thumb,' " he jokes.