The Black Eyed Peas star, who married Duhamel in 2009, revealed that she would like her husband to "keep" his mohawk.
"He's definitely my North Dakota husband, but then he got that mohawk for [the movie] Scenic Route," People quotes Fergie as saying. "He got that rock 'n' roll look and I was very turned on."
Fergie also revealed that she has been able to spend more time with Duhamel recently, saying: "I'm nurturing my relationship with my family, getting to see them more."
Fergie was recently linked to a role as a judge on the upcoming season of The X Factor USA.
However, she has denied the reports, saying: "It's not the right time."