Children whose mothers are overweight are more likely to have higher levels of body fat themselves at age nine

A study, led by Dr Catharine Gale and Professor Cyrus Cooper of the University of Southampton's MRC Epidemiology Resource Centre, published online by the US Journal of Clinical Endocrinology and Metabolism, has found that children whose mothers had a higher pre-pregnancy body mass index (BMI) or had fatter upper arms during late pregnancy, were significantly more likely to have a higher amount of body fat themselves at the age of nine.

'A previous study showed that babies are born with a higher amount of amount of body fat if their mothers were significantly overweight during pregnancy, and we wanted to see whether that relationship persists into childhood,' comments Dr Gale.

'We carried out a whole body scan of 216 nine-year-old children, whose mothers had participated in a study of nutrition during pregnancy. We investigated the relationship between maternal size in pregnancy, early growth and body composition at the age of nine years.

'We found that mothers with a higher pre-pregnant BMI, or a larger mid-upper arm circumference in late pregnancy, tended to have children with greater 'adiposity' or 'fatness', at the age of nine. Although the extent to which this is attributable to genetic factors, the influence of the mother's lifestyle on that of her child, or to physical changes to the child's fat mass brought on by their mother's 'adiposity' during pregnancy, is not yet known.

'We also noticed that children were likely to have greater fat mass if their mothers had smoked in pregnancy, if they had gained a lot of weight in infancy (especially boys), or had not been breastfed (especially girls). '

The increasing prevalence of childhood overweight and obesity in the developed world is widely recognised as a major public health problem, with its increased risks of higher blood pressure, insulin resistance, formation of fatty deposits in the arteries, and obesity in adult life. The results of this research show that a mother's over-nutrition before and during pregnancy may have a persisting and long-term influence on her child's tendency to fatness.