John Cena says he doesn't just want to have kids to win Nikki Bella back -- telling TMZ Sports he's had an epiphany about wanting to have a family outside of his career.
The 41-year-old WWE superstar says he KNOWS his new outlook is a complete "about-face" from what he's been preaching publicly for decades ... but insists it's because he's grown as a person.
"I would love to be a dad," Cena says ... "and I realize very much that I have been steadfast in saying that I don't want children.