Women who improve their health before they become pregnant could reduce their child's risk of becoming obese later in life, a new study indicates.

There is already a growing body of evidence that suggests that a child's life in the womb and soon after birth can affect their risk of obesity. While some studies have identified early life risk factors, most have not looked at the combined effects of these factors.

UK scientists decided to look into this further by assessing five early life risk factors in almost 1,000 children. The risk factors were breastfeeding for less than one month and four maternal factors during pregnancy - smoking, excessive weight gain, obesity and low vitamin D levels.

The study found that the more of these risk factors a child was exposed to, the greater their risk of being overweight or obese later in childhood.

In fact, children exposed to four or five of these factors were almost four times more likely to be overweight or obese by the age of four, compared to children who were not exposed to any of these risk factors.

Meanwhile, the fat mass of these children was 19% higher.

By the age of six, the risk of overweight and obesity had increased even more among these children. It was 4.65 times higher, while their fat mass was almost 50% higher.

The scientists from the University of Southampton emphasised that these differences could not be explained by other risk factors such as the children's exercise levels or diet.

"Early life may be a critical period when appetite and regulation of energy balance are programmed, which has lifelong consequences for the risk of gaining excess weight. Although the importance of early prevention is recognised, much of the focus is on school-aged children.

"Our findings suggest that interventions to prevent obesity need to start earlier, even before conception, and that having a healthy body weight and not smoking at this time could be key," commented lead scientist, Prof Sian Robinson.

Details of these findings are published in The American Journal of Clinical Nutrition.

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