How are psychiatric disorders in children related to infections during pregnancy?

Infections contracted by a pregnant woman during pregnancy can affect the child's development in different ways. Beyond the purely somatic anatomical and physiological alterations, the alteration of certain precursor neuronal cells can lead to the appearance of psychiatric disorders later in the child, particularly in the schizophrenic and autistic spectrum. This is the conclusion of a new study that highlights the severity of infections and the importance of when they occur.


Serious infections during pregnancy have been linked to various psychiatric disorders by different studies conducted in humans and animals. Researchers at the University of Copenhagen have shown in mice how infections affect neuronal development and the timing of infection.

Infections, brain development and psychiatric disorders

The health of the mother is very important for the development of the fetal brain during pregnancy. Many factors play a key role in healthy brain development, including nutrition, stress, hormonal balance, and the mother's immune system.

It has been observed in humans and animals that serious infections in pregnant women are a risk factor for developing psychiatric disorders such as schizophrenia and autism spectrum disorders later in the life of the child.

The authors of the study, published in the journal Molecular Psychiatry, showed how infections in the mother can alter the development of stem cells and neuronal precursors of the brain.

Maternal inflammation affects the development of multi-stage interneurons, such as proliferation, migration, differentiation and maturation, resulting in increased vulnerability to mental disorders. Credits: Navneet A. Vasistha et al. 2019

" The connection has already been made in animal studies and clinical observation studies. However, this is the first time we show how infections during pregnancy affect brain development and can lead to cognitive impairment. Although many factors have been assumed or indicated, it is important to show the stages of neuronal development actually affected, "says Konstantin Khodosevich

Infections: the mother's immune response impairs the brain cells of the child

The researchers studied the development of neurons in mice. The mother's immune response to infection has had an effect that extends from stem cells and precursor cells to neuronal cells, causing a profound disruption of their development in the brain. More specifically, the development of cortical GABAergic interneurons - the class of neurons that allows inhibition in the brain - was impaired.

Infections during pregnancy impair neuronal development, resulting in a decrease in the number of motor and somatosensory (bley) neurons. Credits: Navneet A. Vasistha et al. 2019

The effect was immediate and had profound consequences through lasting alterations, resulting in multiple "impacts" during the neuronal development process - from the birth of neurons to their maturity.

In addition, the researchers also concluded that newborn mice exhibited symptoms similar to those of human psychiatric disorders, including reduced prepulsion inhibition, impaired social interaction, and cognitive decline.

The importance of the moment of infection during pregnancy

" The study in humans poses big technological and ethical problems, because of the vulnerability of pregnant women. This is why we study the functioning of mechanisms in mice. Psychiatric disorders are very complex and for some, we still do not know how they present themselves. We really want to contribute to the scientific understanding of these diseases, "explains Khodosevich.

Depending on the time of infection during pregnancy, different precursor cells and, consequently, different neurons, were affected. This means that the moment of infection is very important and can lead to variable results depending on the stage of development of the affected brain. This can potentially underlie the complexity of psychiatric disorders.

The researchers are now hoping to deepen their knowledge of the molecular mechanisms and signaling pathways that cause the degradation of interneuron development.


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