Babies born to mothers who are overweight or obese already display one of the early signs of heart disease, irrespective of their birth weight, a new study has found.

Australian researchers followed the progress of 23 women from then they were 16 weeks pregnant. Their average age was 35 and their body mass indexes (BMI) ranged from 17 to 42. A BMI of 25 or more is considered overweight, while 30 or more is obese.

Seven days after their birth, the abdominal aorta of each baby was scanned, to determine the thickness of the two innermost walks. The aorta is the body's major artery and the abdominal aorta is the part which reaches down to the belly.

Arterial thickening is a sign of heart disease.

The study found that among the babies, the walls of the aorta were already thickened if their mothers were overweight or obese.

The scientists from the University of Sydney noted that these results were irrespective of the weight of the baby when he/she was born. A high birth weight is a known risk factor for heart disease later on.

In fact, the more the mother weighed, the thicker the arterial wall irrespective of how much the baby weighed when he/she was born.

The scientists suggested that this may explain how overweight mothers increase their children's risk of heart disease later in life.

Details of these findings are published in the journal, Archives of Disease of Childhood.

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