Actress Greta Gerwig discovered her stutter when she was asked to narrate an audiobook.

The Frances Ha star was unaware of her speech impediment until she started work on the project, and she opened up about her troubles during a book reading in New York City this week (beg16Nov15).

Gerwig made the revelation before giving a reading at the launch of a new book at the Jane Hotel in Manhattan, according to New York Post gossip column Page Six.

"I apologize if I stutter," Gerwig told the audience before reading a passage from The Unprofessionals: New American Writing From the Paris Review.

"I actually do tend to stutter, which is a fact I learned too late... After I'd been hired to record an audiobook. They were very gracious. It was a novella, and it took two weeks."