On Monday, the Madison County prosecutor's office in Anderson, Ind., filed criminal charges against the reality star following an on-camera physical altercation with her former fiancé – and the father of her daughter Leah, 2 – Gary Shirley.
Portwood, 20, has been charged with three class D felonies, including two counts of domestic battery and one count of neglect of a dependent. She was also charged with one misdemeanor charge of domestic battery. Portwood faces up to three years in jail if convicted.
A rep for MTV had no comment on the case.
In a September interview with PEOPLE, Portwood expressed regret about the fight – especially because one day, she said, Leah might watch it on television.
"I don't want her to see that and think that it's okay," Portwood explained at that time, adding that she and Shirley were working to make sure that their fights never became physical again. "We just kind of made that decision because of Leah. We see it affecting her."
Portwood even wore a ring Shirley gave her as a symbol of their commitment to stop fighting.
"It's more of a promise ring that we're trying not to fight anymore," she said of the bauble. "We both just need to calm down in our personalities. We were clashing too much."
Teen Mom 2, which will follow four new young mothers, will premiere Jan. 11 on MTV.