Does Twin or Multiple Birth Status Influence Autism Risk?

PostedDecember 2, 2025

UpdatedDecember 2, 2025

ByMy Patient Advice

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

Yes, studies suggest that multiple birth and autism risk are connected, with twins and other multiples showing a slightly elevated likelihood of autism compared to single-born children. While not all multiple births carry the same level of risk, the unique conditions of these pregnancies, such as prematurity or low birth weight, are known contributors.

Research into multiple birth and autism risk often focuses on shared factors, including perinatal stress, which is more common when two or more babies are developing in the womb. Complications such as limited placental function, restricted growth, or extended neonatal care are frequent in multiple births, and each of these factors may influence brain development.

Much of what we know about twins and autism comes from large-scale tracking of identical and fraternal twins, which helps separate genetic influences from environmental ones. These studies also examine plurality effects, showing that risk can differ based on whether children share a placenta or experience unequal birth conditions, key contributors to developmental differences.

Why Birth Context Matters

Understanding how birth order and pregnancy type impact development helps guide screening and support efforts. Here’s what we’re learning:

Early tracking for multiple births

Due to the increased vulnerability associated with multiple birth and autism risk, twins and other multiples may benefit from regular developmental checks, even before signs of delay appear.

Broader insights through twin research

By studying twins, researchers can better understand how both genetics and early environment influence autism, creating pathways for more tailored early care.

Acknowledging the link between multiple birth and autism risk helps ensure that families with multiples are equipped with knowledge and timely support. Visit providers like Autism Detect for expert guidance on early assessment and planning.

For a deeper dive into the science, diagnosis, and full treatment landscape, read our complete guide to Birth Complications and Low Birth Weight.

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.