Are maternal thyroid disorders environmental factors associated with autism?

PostedNovember 26, 2025

UpdatedNovember 26, 2025

ByMy Patient Advice

Author: Lucia Alvarez, MSc | Reviewed by: Dr. Rebecca Fernandez, MBBS

Yes, maternal thyroid disorders & autism may be linked, with research suggesting that thyroid imbalances during pregnancy can serve as an environmental factor influencing a child’s neurodevelopment. While the exact relationship is still being studied, both underactive (hypothyroidism) and overactive (hyperthyroidism) thyroid conditions have been associated with increased autism risk.

Thyroid hormones play a crucial role in early brain development, particularly during the first trimester when the foetus relies entirely on maternal hormone supply. Disruptions to this delicate balance can impact brain structure, connectivity, and function.

How Maternal Thyroid Disorders Might Influence Autism Risk

Here are two ways maternal thyroid disorders may contribute to an environmental link with autism:

Hormonal imbalance during critical development windows

Insufficient levels of thyroid hormones can impair the growth of key brain regions, such as those involved in language and social interaction. This may increase the likelihood of autism-related traits appearing later.

Compromised placental hormone transfer

Thyroid disorders may interfere with the efficient transfer of essential hormones from mother to foetus, particularly in early pregnancy. This can result in subtle but meaningful developmental differences.

Recognising maternal thyroid disorders & autism as potentially linked supports the importance of early screening and thyroid management in prenatal care. 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.