Beyonce's pregnancy may postpone the making of A Star Is Born.
Following the singer's announcement at the MTV VMAs in Los Angeles, the musical remake - to be directed and produced by Clint Eastwood with Warner Bros - may have to be put back, reported Deadline.
Production was scheduled to start in February 2012, but insiders told the website that "it could be pushed back".
A male co-star to take the lead opposite Beyonce has yet to be found, following Leonardo DiCaprio's exit from the role, with Will Smith and Christian Bale said to be in the running.
Beyonce - who proved her acting chops in Oscar-winning musical Dreamgirls and Cadillac Records - will take on the role of up-and-coming starlet Esther Blodgett, previously played by Barbra Streisand and Judy Garland in the 1976 and 1954 adaptations, and Janet Gaynor in the 1937 original.
The star debuted her baby bump in an orange Lanvin gown, saying: "I have a surprise!" and later performed on stage, rubbing her bump and told the audience: "I want you to feel the love that's growing inside of me."
It is her first child with rapper husband Jay-Z, who she married in September 2008.
Beyonce recently revealed she felt ready to settle down and start a family, following her career achievements.
"When you're young - 18 or 19 - you have the energy and drive. That's the time to work as hard as you can," she told InStyle.
"Now I'm a woman, and because I gave it my all, I can focus on my marriage. I can decide I want to have kids. I can be the mother I want."