Pop star Pink has poked fun at rumors she's expecting her first child with husband Carey Hart by joking about having a "600 pound baby."
 
The hitmaker, real name Alecia Moore, sparked reports she was pregnant after she was snapped with a slight tummy bump earlier this week.
 
The singer has so far refused to confirm or deny the claims, but took to Twitte on Thursday to suggest the renewed baby speculation is just the latest in a longrunning joke.
 
She wrote, "Off to the gym. Lord knows when this 600 pound baby comes out that I've been growing for 8 years, i better be strong and physically prepared!!!"
 
Pink reunited with motocross racer Hart last year after a year of estrangement. They wed in 2006.