Can maternal infections as environmental factors contribute to autism? 

Yes, growing research indicates that maternal infections & autism may be connected. Infections during pregnancy are now considered possible environmental factors that could influence a child’s neurodevelopment and increase autism risk. While not all infections lead to complications, certain viral or bacterial illnesses may trigger immune responses that affect the developing brain. 

The body’s natural immune reaction to infection can release inflammatory molecules that cross the placenta. These immune signals can potentially disrupt brain development in the foetus, particularly if the infection occurs during the first or second trimester, when critical brain structures are forming. These pregnancy effects may be subtle but could shape long-term neurological outcomes. 

How Maternal Infections Might Influence Autism 

Here are two ways maternal infections during pregnancy may affect autism risk: 

Immune activation during pregnancy 

When a pregnant person contracts an infection, their immune system becomes activated. This activation may alter the environment in the womb, with potential impacts on how brain cells grow, connect and organise. 

Changes in hormone and cytokine levels 

Infections can shift hormone balances and increase levels of cytokines, which are signalling proteins involved in immune function. Elevated cytokine levels have been linked to changes in early brain development associated with autism. 

The connection between maternal infections & autism highlights the importance of preventive healthcare during pregnancy, including timely vaccination and infection management. Visit providers like Autism Detect for personal consultations and further guidance on screening and support. 

For a deeper dive into the science, diagnosis, and full treatment landscape, read our complete guide to Environmental Factors. 

Lucia Alvarez, MSc

Author

Lucia Alvarez is a clinical psychologist with a Master’s in Clinical Psychology and extensive experience providing evidence-based therapy and psychological assessment to children, adolescents, and adults. Skilled in CBT, DBT, and other therapeutic interventions, she has worked in hospital, community, and residential care settings. Her expertise includes grief counseling, anxiety management, and resilience-building, with a strong focus on creating safe, supportive environments to improve mental well-being.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the author's privacy. 

Dr. Rebecca Fernandez, MBBS

Reviewer

Dr. Rebecca Fernandez is a UK-trained physician with an MBBS and experience in general surgery, cardiology, internal medicine, gynecology, intensive care, and emergency medicine. She has managed critically ill patients, stabilised acute trauma cases, and provided comprehensive inpatient and outpatient care. In psychiatry, Dr. Fernandez has worked with psychotic, mood, anxiety, and substance use disorders, applying evidence-based approaches such as CBT, ACT, and mindfulness-based therapies. Her skills span patient assessment, treatment planning, and the integration of digital health solutions to support mental well-being.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the reviewer's privacy.