The Scottish Extras actress is due to give birth in the autumn, and has said she is "excited" about the new arrival.
Reports of a baby began to circulate after pictures emerged at the start of the month of Ashley walking her dogs displaying what appeared to be a baby bump.
Previously, pictures of the 39-year-old with a swollen midriff had been attributed to her Ugly Betty character, Christina, who became pregnant in the series.
Her on-screen persona recently returned to her native Scotland with her child, although she looks set to come back to the show.
When Ashley was asked last year if her success on Ugly Betty meant she was delaying starting a family, she said: "If I get pregnant, I get pregnant. They'll either deal with it or they'll recast me."
The blonde star married British actor and writer Terence in Big Sur, California, in 2007 - at a private ceremony only attended by their dog Barney, who acted as the ring-bearer. The couple got together after appearing in a London stage production of King Lear.