The show began its third season on ABC Family in June.
"It was right up my alley," Palin told the Los Angeles Times. "I was pregnant the same time as the character, Amy, on the show, so I kind of felt like we went through the experience together."
Palin, 19, became possibly the most famous pregnant teenager in the country when her mother was nominated by the Republican Party for vice president in 2008. She is now a spokeswoman for teenage abstinence.