Since 2006, UFZ researchers have been cooperating with colleagues from Klinikum St. Georg gGmbH and the Universitätsklinikum Leipzig in the LiNA study: LiNA stands for "lifestyle and environmental factors and their influence on newborns allergy risk". In the current study, the researchers led by Irina Lehmann and Saskia Trump, both of whom have joined the BIH in the beginning of 2018, evaluated data from 498 mother-child pairs. They studied the perceived distress of mothers during pregnancy and the two consecutive years after birth with validated questionnaires that assessed issues like worries and anxiety, tension, overall satisfaction and dealing with daily hassles. Maternal stress was then linked to children`s body mass index (BMI) normalized to age and sex.
Stressed mothers are more likely to have overweight children than relaxed mothers.
"We observed that the perceived stress of the mother during the first year after birth clearly was associated 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. Interestingly, neither maternal stress during pregnancy nor after children’s age of one showed an effect on the children’s BMI. "The first year of life seems to be a sensitive period and has a lasting impact on overweight development," 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 evaluate why the mothers were stressed during pregnancy and during the first two years of children’s life, we had a closer look at the data," 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 a lower household income.
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 problems." Paediatricians should also pay attention to the mothers during the regular child examinations in particular in the first year after birth and evaluate them with respect to their situation and whether there are signs of stress. "There are already existing initiatives to support mothers, but only a few mothers are aware of them. If you can address these mothers early on, you could do both: help the mothers and thus possibly lower the risk of their children to become overweight," said Saskia Trump. In the future, the team wants to investigate which other risk factors can influence children’s weight development and which mechanisms might be involved in long-lasting malfunctions 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.