Beyonce Knowles wants to "stay busy" during her pregnancy.

The 'Best Thing I Never Had' hitmaker - who turns 30 today (04.09.11) - is currently four months pregnant with her first child with music mogul Jay-Z, but intends to keep working.

A source told the Mail on Sunday: "Beyonce wants to stay busy. She plans to take part in a Michael Jackson tribute concert in October at Cardiff's Millennium Stadium via satellite link, and although she'll take time off after the birth, she's committed to her role in Clint Eastwood's film 'A Star Is Born' and to launching a perfume next year."

Beyonce - who has always claimed she would get pregnant by the time she turned 30 - announced her pregnancy at the MTV Video Music Awards while performing her song 'Love on Top' urging the crowd to "feel the love" inside of her before taking off her jacket to reveal her growing baby bump.