Actress Hayden Panettiere has confirmed she is pregnant by nominating her "unborn child" for the ALS Ice Bucket Challenge.

The Nashville star finally acknowledged she and fiance Wladimir Klitschko are preparing for their first child on Wednesday (20Aug14) by posting footage of pal and co-star Derek Hough tipping a bucket of freezing water over her on Instagram.com.

Panettiere prepared for the cold blast by nominating country singer Kacey Musgraves, her fiance and her "unborn child" to take the challenge next.

The actress follows in the footsteps of Guardians of the Galaxy star Zoe Saldana, who also confirmed she is pregnant in an Ice Bucket Challenge video posted on Tuesday (19Aug14). She opted to dodge the challenge set her by director James Gunn, and her husband Marco Perego agreed to take the plunge in her place.

Celebrities including Panettiere's Nashville co-star Connie Britton, Robert Pattinson, Emily Blunt and Adam Sandler all recently took the Ice Bucket Challenge to raise cash and awareness for charity the ALS Association.