Women who gain too much weight during pregnancy could be condemning their child to an increased risk of early onset bowel cancer decades later, experts warn.

'We know that some early life exposures - including maternal obesity and excessive weight gain during pregnancy - may increase the risk of early onset colorectal cancer,' Dr Rosiered Brownson-Smith, an expert in the risks associated with diet, lifestyle and health, at King's College London, said.

'This can change the trajectory of a child's life, potentially predisposing them to some early susceptibility that will only come to fruition later in life.'

Her remarks follow a sharp rise in the number of young people diagnosed with the disease, with more than 2,700 cases among young people every year in the UK.

It has long been suggested that a mother's health profile can have a lasting effect on their offspring's health. But experts have suggested that later life exposures, such as smoking, are more important when it comes to cancer risk.