A 43 stone US lady has a giant-sized ambition - to be the world's heaviest woman.Donna Simpson, 44, from Old Bridge, New Jersey, who is 5ft 4ins tall, has a target weight of 72 stone.To do so she consumes up to 12,000 calories a day, eating up to 70 pieces of sushi - her favourite food - at one sitting.Mrs Simpson says her weight gain began when her first husband, a chef, encouraged her to eat, bringing home leftovers from work.When they divorced, shortly after she gave birth to their son Devin, she piled on the pounds. A few years later she decided to try and lose weight and managed to drop five stone in six months.She was even due to have a gastric band operation until a friend died during a similar operation. Since then, she has only tried to gain rather than lose weight.She met her current boyfriend - 13st, 6ft 4ins Philippe Gouamba - in an online chat room for oversized women in 2006.Despite doctors telling her it would be almost impossible for her to conceive, Mrs Simpson fell pregnant within months of their meeting.A total of 19 doctors and nurses were on hand when her daughter Jacqueline was born via Caesarean in February 2007.The birth meant Mrs Simpson, who then weighed 38st, officially became the world's heaviest mother.Source: orange.com