A new study suggests activation of a mother’s immune system during pregnancy, such as during an allergic response, may affect foetal brain development. This could influence the child’s susceptibility to psychiatric disorders in later life, such as autism, schizophrenia and attention deficit hyperactivity disorder.
Published in the Journal of Neuroscience, the study found a relationship between two proteins released by a mother’s immune system during the third trimester of pregnancy and the way a certain brain network involved in the above disorders developed in the infants.
Another study published last year suggested activation of the mother’s immune system during pregnancy could influence long-term child mental health and developmental disorders, specifically autism. These studies add to growing evidence linking a significant immune response - such as one that develops during flu or food poisoning – in pregnancy to negative outcomes for the woman’s offspring later in life.
Researchers have termed this exaggerated immune responses in pregnancy, which is potentially detrimental to the foetus, as “maternal immune activation” (MIA).
The immune response.
The immune system can be thought of as an army. When an infectious agent such as a virus or bacterium invades our body, it can result in illness or fever. Our immune system recognises these danger signals and mounts an attack of its own. This attack, known as the immune response, is carried out by immune molecules and cells that work to neutralise and eliminate threats.
In most situations, the immune response protects the body from illness. But it can also be negative in some cases, such as in autoimmune diseases like diabetes (type one), rheumatoid arthritis and multiple sclerosis. In diabetes, a misdirected immune response causes immune molecules to attack the pancreas and reduce insulin-producing cells.
It’s well established the womb environment is important for the baby’s healthy development. This environment is generally stable and well balanced, monitored by the many systems that support well-being, including the nervous and immune systems. When maternal immune activation occurs, this balance is believed to be disrupted.