GWEN STEFANI - STEFANI WORKED OUT WHILE PREGNANT

Pop star GWEN STEFANI was so desperate to lose weight after giving birth, she started working out with a personal trainer while still pregnant. The singer admits she has an obsession with her weight and only stopped exercising two weeks before son KINGSTON was born last May (06). And she reveals her work outs were so rigorous she would often break down in tears. Stefani, 37, tells Elle magazine, "I worked out with my trainer throughout the whole pregnancy until about two weeks before. "I cried during my last session. I was like, 'I can't breathe, I can't do this any more. What am I doing?' It was crazy. All of my life I've had to work hard to stay in shape. I've always struggled with it. I was a little chubby when I was younger and I didn't want to be that person forever. "There aren't any tricks, it's simple math - you put this much food in, you burn that much working out. "I gave myself three months - but if I didn't have an album coming out, there's no way I would have got back into shape in that time. I worked out with my trainer five days a week, with weekends off. I would really recommend doing weights."