Hilary Duff, "overwhelmed"

Hilary Duff has said she is "overwhelmed" by the messages of congratulations she has received since announcing her first pregnancy.

The former Lizzie McGuire star and husband Mike Comrie revealed that they are expecting a baby on the same day that they celebrated their first wedding anniversary over the weekend.

Posting on Duff's official website, they said: "Baby Makes Three!!! We are extremely happy and ready to start this new chapter of our lives."

Writing on her Twitter account following the announcement, the actress added: "Wow! I am just overwhelmed by all of the wonderful messages everyone is sending! Thank you so much! Big hugs!"

Duff's older sister Haylie was one of the many well-wishers who posted their congratulations on Twitter, writing: "Congrats to my sissy @HilaryDuff and my B.I.L Mike on their 1 year anniversary and the tiny new addition :)"

Fellow Disney star Ashley Tisdale also congratulated Duff and Comrie on her own Twitter feed, saying: "So excited for @HilaryDuff and Mike!"

Duff and Comrie began dating back in 2007 and tied the knot at a ceremony in Santa Barbara, California last summer.

Hilary Duff Backless in Black Bikini at Pool

Hilary Duff black bikini candids enjoying at sea

Hilary Duff : Good Housekeeping 125th Anniversary in NYC

Hilary Duff stepped out in a  style to celebrate Good Housekeeping magazine's 125th anniversary on Monday 12th of April 2010. The 22-year old showed off her stylist side in a black tulle one-shouldered confection by Vera Wang and was looking like a diva while she was attending the "Shine On" held in the New York. She was simply rocking.