In the mother-child study LiNA, which is coordinated by the UFZ, they found that the perceived stress of the mother in the first year of life of the child promotes overweight in infancy. Furthermore, the researchers of the BIH, the Charité, the UFZ and the University of Bristol report in their recently published study in the BMC Public Health journal that maternal stress does mainly affect the long-term weight development of girls.
Since 2006, UFZ researchers have been cooperating with colleagues from the St. Georg Municipal Hospital and the University Hospital Leipzig in the LiNA study: LiNA stands for "lifestyle and environmental factors and their influence on the risk of allergies of newborns". In the current study, the researchers led by Irina Lehmann and Saskia Trump, both of whom have been conducting research at the BIH since the beginning of 2018, evaluated data from 498 mother-child pairs. Based on the information on size and weight, the researchers determined the body mass index (BMI) of the children and normalized it to age and sex. They assessed the perceived distress of mothers during pregnancy and the children's first two years of life with validated questionnaires that included issues of worry and anxiety, tension, overall satisfaction and dealing with daily needs. Then they put both records in relation to each other.
Stressed mothers are more likely to have overweight children than relaxed mothers.
"We have seen that the perceived stress of the mother during the first year of life of the child clearly cohered with the weight-development of the child during the first five years of life," says Irina Lehmann, who designed and directed the study together with Saskia Trump. "Stressed mothers are more likely to have overweight children than relaxed mothers." "The influence of maternal stress on girls is especially noticeable," adds Saskia Trump. Studies have shown that boys may better compensate for mothers' stress. There was no effect on the children's weight by maternal stress during pregnancy or during the second year of childhood. "The first year of life seems to be a sensitive period and a mark on the tendency to be overweight," says Kristin Junge from the UFZ, one of the first authors of the study. "During this time, special attention should be paid to the well-being of the mother," she adds.
Causes of maternal stress
"In order to find out why the mothers were stressed during pregnancy and during the first two years of the life of their children, we had a closer look at the data again" reports Beate Leppert, also first author of the study, who now works at the University of Bristol. "In particular, we looked at mothers' living conditions." The researchers discovered that stressed mothers were more likely to live in a poor living environment than unstressed mothers, were more exposed to noise and road traffic, and on average had lower household incomes.
Do not leave stressed mothers alone
"We want to draw attention to the problem of stressed mothers with our study," says Irina Lehmann. "By no means one should leave them alone with their problem." Paediatricians could always look at the mothers in the first year of their children's examinations and address them to their situation if there are signs of stress. "There are already existing offers of help for mothers, but only a few of them are aware of it. If you can address these mothers early on, you could do both: help the mothers and thus possibly lowering the risk of their children being overweight," said Saskia Trump. In future research work, the team wants to investigate which other risk factors can influence the child's weight development and which mechanisms are involved in the long-lasting misdirection of the metabolism.
Leppert B, Junge KM, Röder S, Borte M, Stangl GI, Wright RJ, Hilbert A, Lehmann I, Trump S.: Early maternal perceived stress and children's BMI: longitudinal impact and influencing factors. BMC Public Health. 2018 Oct 30; 18(1):1211. doi: 10.1186/s12889-018-6110-5.