Pregnancy stress may spark obesity

Stress during pregnancy may programme an unborn child for obesity, research has suggested.

Pregnant mice fed a low-protein diet gave birth to female offspring that rapidly put on weight and developed early signs of diabetes, a study found, and laboratory tests indicated that the fattening effect was caused by the genetic impact of stress hormones.

The same changes were not observed in male offspring, which appeared to grow normally, and the scientists believe their findings in mice has implications for humans.

Dr Ruijun Han, who led the US team from the University of Minnesota, said: “Intervention during pregnancy and childhood might be an efficient way to prevent adult obesity.”

The scientists focused on a nerve signalling molecule, or neurotransmitter, called NPY which is linked to appetite and the storage of energy as fat.

NPY exerts its effects by latching on to another “receptor” molecule, Y2R. The researchers wanted to see if stress had any effect on NPY or its receptor.

First they exposed pregnant mice to stress by feeding them a low-protein diet.