IVF and Autism: What the Science Says
As IVF and other fertility treatments have become more common, many prospective parents understandably wonder about long-term outcomes for their children. One of the most frequently asked questions is whether IVF increases the risk of autism spectrum disorder (ASD).
The best available scientific evidence offers clear reassurance: **IVF does not cause autism.**
While some headlines suggest fertility treatments may significantly increase autism risk, these claims rely on misleading interpretations of statistics.
Extensive, well-designed studies consistently show that when small differences in autism rates are observed, they are linked to underlying infertility, parental age, and pregnancy-related factors, not the IVF process itself.
Below is an evidence-based explanation of what the research and statistics actually reveal.
Quick Answer: Does IVF Increase Autism Risk?
- IVF and ICSI do not increase autism risk when appropriate parental, medical, and pregnancy factors are taken into account.
- Children born to individuals with infertility may have slightly higher autism rates, whether or not fertility treatment is used.
- Observed differences are explained by parental age, underlying medical conditions, and pregnancy outcomes, not IVF itself.
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Why Some Headlines About “Increased Risk” Are Misleading
Some articles report large percentage increases in autism risk after fertility treatment. While these numbers may appear alarming, they typically reflect relative risk rather than the absolute number of children affected.
In large population studies, autism is diagnosed in only a small percentage of children overall, regardless of how they were conceived. Even when one group shows a higher percentage than another, the actual difference often amounts to fewer than one additional diagnosis per 1,000 children.
This is why researchers emphasize absolute risk and careful adjustment for confounding factors rather than headline-grabbing percentages.
What the Largest Studies Show
Ontario Study (2023): Over 1.3 Million Children
The largest and most comprehensive study to date examined more than 1.3 million children in Ontario, Canada. Researchers compared autism rates among :
Children conceived without infertility
Children born to individuals with infertility who did not use treatment
Children conceived using fertility treatments, including IVF and ICSI
The study found that:
- Autism rates were slightly higher among children born to individuals with infertility
- Rates were similar whether or not fertility treatment was used
- After accounting for maternal and paternal age, medical conditions, multiple pregnancy, premature birth, cesarean delivery, and newborn complications, IVF itself did not explain the observed differences
The authors concluded that infertility and pregnancy-related factors, not fertility treatment, account for the small differences seen in autism rates.
Massachusetts MOSART Study (2019): Over 460,000 Births
A large U.S. population-based study using Massachusetts health data also examined autism outcomes in over 460,000 children born to :
- Fertile individuals
- Individuals with infertility who did not use fertility treatment
- Individuals who conceived using IVF or ICSI
Using advanced statistical and mediation analyses, the study found:
- No increased autism risk associated with IVF, ICSI, or ART overall
- No increased risk among individuals with infertility compared with fertile controls
- No evidence that fertility treatment caused autism
The authors concluded that children conceived through IVF or ICSI are not at increased risk of receiving an autism diagnosis.
How Infertility-Related Factors, Not IVF, Explain Small Differences in Autism Rates
Across large population studies, small differences in autism rates are sometimes observed among children born to individuals with infertility.
Importantly, these differences do not reflect an independent effect of infertility itself, but rather the influence of parental and pregnancy-related factors that are more common in infertility populations.
Factors most consistently associated with autism risk include:
- Underlying medical or hormonal conditions, such as polycystic ovary syndrome (PCOS), which are more common among individuals with infertility
- Higher rates of pregnancy and newborn complications, including premature birth and neonatal morbidity
When these factors are properly accounted for, large studies show no increased autism risk associated with infertility, IVF, or ICSI.
IVF does not create these factors, it helps individuals who already have these co-morbidities conceive.
Do Specific IVF Procedures Increase Autism Risk?
Ovarian Stimulation and Embryo Culture
Some concerns have been raised about whether fertility medications or embryo culture techniques could influence neurodevelopment. Large cohort and molecular studies have not shown evidence that these steps increase autism risk.
While small biological differences have been observed at the molecular level, they have not been linked to autism diagnoses.
ICSI (Intracytoplasmic Sperm Injection)
ICSI is commonly used for male-factor infertility. When researchers account for paternal age, sperm factors, and pregnancy outcomes, ICSI is not associated with increased autism risk.
Pregnancy and Birth Factors Matter More Than Method of Conception
Pregnancy, birth, and parental factors are among the strongest predictors of autism across all children, regardless of how they were conceived.
These include:
- Advancing maternal and paternal age
- Premature birth
- Twins or triplets
- Serious newborn medical complications
These factors are more common among individuals with infertility, which helps explain observed differences in autism rates. Importantly, they are not caused by IVF.
Fresh vs. Frozen Embryo Transfer
Large studies comparing fresh and frozen embryo transfers, as well as standard IVF versus IVF with ICSI, show no meaningful difference in autism risk after appropriate adjustment for parental and pregnancy-related factors.³
IVF and Autism: The Bottom Line
After decades of research and analysis of millions of births worldwide, the conclusion is clear:
- **IVF does not increase the risk of autism.**
- Small differences seen in studies are explained by infertility, parental age, and pregnancy-related factors, not fertility treatment.
- Children conceived through IVF have the same likelihood of autism as those conceived naturally when these factors are considered.
For individuals and couples considering IVF, the evidence is genuinely reassuring.
Frequently Asked Questions
Does IVF cause autism?
No. Large, well-designed studies show that IVF itself does not cause autism. When small differences in autism rates are seen, they are explained by infertility, parental age, and pregnancy-related factors, not fertility treatment.¹²
Is autism more common in children conceived through IVF?
Children born to individuals with infertility may have slightly higher autism rates, but this increase is seen regardless of whether fertility treatment is used. Studies comparing IVF, ICSI, and natural conception do not show a meaningful increase in autism risk caused by IVF.
Why do some articles say IVF increases autism risk by large percentages?
These reports usually focus on relative risk, which can sound dramatic. In real-world terms, autism remains uncommon, and the absolute difference between groups is typically fewer than one additional diagnosis per 1,000 children.
Does ICSI increase autism risk?
No. When studies properly adjust for male-factor infertility, parental age, and pregnancy outcomes, ICSI is not associated with increased autism risk.
Does freezing embryos increase autism risk?
No. Large studies comparing fresh and frozen embryo transfers show no meaningful difference in autism risk once parental and pregnancy-related factors are considered.
Does maternal age increase autism risk?
Yes. Advancing maternal and paternal age are among the strongest and most consistently identified risk factors for autism, regardless of how a child is conceived.
Do pregnancy complications affect autism risk?
Certain pregnancy and newborn factors—such as premature birth, twins or triplets, and serious neonatal complications—are associated with higher autism risk. These factors help explain small differences seen in population studies and are not caused by IVF.
What should prospective IVF patients take away from this research?
The best available evidence shows that IVF does not increase autism risk. Small differences seen in studies are explained by infertility, parental age, and pregnancy-related factors, not fertility treatment itself.
