Summary: Mothers who reported stress during pregnancy reported their child experienced behavioral problems between the ages of 7 and 8. However, behavioral problems were reduced if the child had older siblings.
Source: Max Planck Institute
In a new study, a Leipzig-based team of researchers including scientists from the Helmholtz Centre for Environmental Research (UFZ), Leipzig University (UL), the MPI for Evolutionary Anthropology (MPI EVA) and the German Centre for Integrative Biodiversity Research (iDiv) used longitudinal data from the LINA (Lifestyle and environmental factors and their Influence on the Newborn Allergy risk) cohort to test 373 German mother–child pairs, from pregnancy until 10 years of age.
Mothers were asked to fill in three validated questionnaires, to assess their stress levels and their child’s behavioral problems.
First, the researchers assessed which social and environmental factors were linked to an increase in maternal stress levels during pregnancy, and the long-term consequences of maternal stress on the occurrence of child behavioral problems.
Second, the researchers assessed whether the presence of siblings had a positive effect on the occurrence of child behavioral problems, by directly reducing stress levels and increasing children’s psychological well-being, or by indirectly buffering the negative consequences of maternal stress.
Prenatal stress can cause behavioral problems in the child
The results of the study demonstrated that socio-environmental stressors, like the lack of sufficient social areas in the neighborhood, were clearly linked to an increase in maternal stress levels during pregnancy.
Moreover, mothers who had experienced high-stress levels, like worries, loss of joy or tension, during pregnancy were also more likely to report the occurrence of behavioral problems when their children were 7, 8 or 10 years old.
“These results confirm previous findings about the negative impact that even mild forms of prenatal stress might have on child behavior, even after several years, and highlight the importance of early intervention policies that increase maternal wellbeing and reduce the risks of maternal stress already during pregnancy,” explains Federica Amici (UL, MPI-EVA), one of the researchers involved in the project.
On a more positive note, the study also found a lower occurrence of behavioral problems in children with older siblings.
“Children who have older brothers or sisters in their households are less likely to develop problems, which suggests that siblings are crucial to promote a healthy child development,” explains Gunda Herberth (UFZ), coordinator of the LINA study.
Higher social competence thanks to older siblings?
This study further suggests that the presence of older siblings directly reduced the likelihood of developing behavioral problems, but did not modulate the negative effects of maternal stress on child behavior.
How could older siblings reduce the occurrence of behavioral problems in children? By interacting with their older siblings, children may develop better emotional, perspective-taking, and problem-solving skills, which are linked to higher social competence and emotional understanding.
Moreover, the presence of older siblings may provide learning opportunities for parents, who might thus develop different expectations and better parental skills.
“We were especially impressed by the important role that siblings appear to play for a healthy child development,” concludes Anja Widdig (UL, MPI-EVA, iDiv).
“We hope that our findings will draw attention to the importance of public health policies that directly target children and their siblings, and promote a healthy environment for their well-being and the development of high-quality sibling relationships”.
Maternal stress, child behavior and the promotive role of older siblings
In the first years of their lives, children develop the cognitive, social and emotional skills that will provide the foundations for their lifelong health and achievements. To increase their life prospects and reduce the long-term effects of early aversive conditions, it is therefore crucial to understand the risk factors that negatively affect child development and the factors that are instead beneficial. In this study, we tested (i) the effects of different social and environmental stressors on maternal stress levels, (ii) the dynamic relationship between maternal stress and child behavior problems during development, and (iii) the potential promotive (i.e. main) or protective (i.e. buffering) effect of siblings on child behavior problems during development.
We used longitudinal data from 373 mother–child pairs (188 daughters, 185 sons) from pregnancy until 10 years of age. We assessed maternal stress and child behavior problems (internalizing and externalizing) with validated questionnaires, and then used linear mixed models, generalized linear mixed models and longitudinal cross-lagged models to analyze the data.
Our results showed that higher maternal stress levels were predicted by socio-environmental stressors (i.e. the lack of sufficient social areas in the neighborhood). Moreover, prenatal maternal stress reliably predicted the occurrence of behavior problems during childhood. Finally, the presence of older siblings had a promotive function, by reducing the likelihood that children developed externalizing problems.
Overall, our results confirm the negative effects that maternal stress during pregnancy may have on the offspring, and suggest an important main effect of older siblings in promoting a positive child development.