Babies of mothers with higher body mass index (BMI) before pregnancy give birth to fatter babies with more fat in their liver, finds a new study.
The researchers from Imperial College London said that the effect of a mother's BMI on her child's development in the womb might put them on a trajectory towards lifelong metabolic health problems.
The research team used magnetic resonance scanning to assess 105 babies born at Chelsea and Westminster Hospital. They found that liver cell fat in the babies and total fat, particularly around the abdomen, increased across the entire range of BMI in their mothers.
The authors of this new study have suggested that the changes they found in babies' bodies might be signs of the first biological changes which, combined with an unhealthy lifestyle, might put babies of overweight mothers on a path to ill health in later life.
"This study demonstrates that a woman's BMI, even in the normal range, affects the amount of fat in her baby at birth," said Professor Neena Modi, from the Department of Medicine at Imperial College London and a Consultant Neonatologist at Chelsea and Westminster Hospital, who led the study.
"Fatter women have fatter babies and there is more fat in the babies livers. If these effects persist through childhood and beyond, they could put the child at risk of lifelong metabolic health problems.
"There is growing evidence that a baby's development before birth has a major impact on their health in later life. This means that the prevention of obesity needs to begin in the womb.
"Today about half of all women of childbearing age in the UK are overweight or obese.
"Importantly, the link between maternal BMI and amount of fat in the baby spreads across the entire range of BMI, meaning it's not just an issue for overweight and obese mums.
"We need to identify what the optimal BMI for the mother is so we can help women ensure that their bodies are in the best possible condition before they get pregnant," added Modi.
The study has been published in September's issue of the journal Pediatric Research.