Obesity and diabetes risks may begin in womb

New research has found that a child’s risk of obesity and type 2 diabetes could start before birth by being pre-programmed in their mother’s womb.
While it is known that children born to obese and diabetic mothers are already more likely to develop type 2 diabetes and obesity in adulthood, independent of their genetic background, the reason is unclear.
Environmental and genetic mechanisms are thought to be involved, including the so-called foetal programming system, whereby the mother’s exposure to environmental factors can affect gene programming in her unborn child.
To investigate further, scientists in Germany set out to show that the post-meal metabolism of a pregnant woman impacts the brain activity of the foetus.
Oral glucose tolerance tests, which involve taking a sugary drink, were conducted on a group of 13 healthy pregnant women and levels of glucose and insulin were measured at 0, 60 and 120 minutes to determine their insulin sensitivity. Sound tests were also carried out at each time point to test foetal brain responses.
After 60 minutes, the results showed that women who were less sensitive to insulin, or more insulin-resistant, had foetuses that reacted more slowly to the sound test. This indicates that foetal brain reactions to the mother’s sugar intake is associated with the latter’s insulin sensitivity.
“It is possible that insulin-resistant mothers have higher glucose levels accompanied by increased insulin levels after a meal,” research author Dr Hubert Preissl, from the University of Tubinge, said. “As glucose passes the placenta, these increased glucose levels induce excess insulin in the foetus. So, high insulin levels in the mother may correspond to high insulin levels in the foetus.”
The scientists concluded: “Lower maternal insulin sensitivity is associated with slower foetal brain responses. These findings provide evidence of a direct effect of maternal metabolism
on foetal brain activity and suggest that central insulin resistance may be programmed during foetal development.”
The research is published in the journal Diabetologia.