PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

No sex differences in autistic toddlers at time of first diagnosis, study finds

A new study from UC San Diego School of Medicine reports no clinical differences in core autism traits between female and male autistic children aged 12-48 months.

2025-05-26
(Press-News.org) Males are more than four times more likely to receive an autism diagnosis than females. But a new study by researchers at UC San Diego School of Medicine has found no clinical differences in autistic traits between the sexes in toddlers when they are first diagnosed with autism. The study was published in Nature Human Behavior on May 26, 2025. The findings have potential implications for early diagnosis and intervention for autistic children.

Between 2002 and 2022, the researchers assessed more than 2,500 male and female toddlers between 12 and 48 months of age. Of these toddlers, 1,500 were autistic, 600 were typically-developing, and 475 were developmentally delayed. The assessments included 19 different measures of language development, social and motor skills, core autism traits such as repetitive behaviors, cognitive skills, and other developmental characteristics. The study also examined social attention using eye tracking technology. All assessments were conducted at a single site — the UC San Diego Autism Center of Excellence — by licensed clinical psychologists.

The researchers found:

No clinical differences between male and female autistic toddlers on all but one of the metrics. The sole exception was a measure of daily living skill development based on parent reporting, such as getting dressed and feeding themselves, which females scored just slightly higher on than males. When clustered into low, medium and high-ability subtypes across the autism spectrum based on robust state-of-the-art methods, there were also no major clinical differences between males and females within these subtypes. No clinical differences between the sexes between 12 and 48 months when the researchers followed the trajectory of development in autistic toddlers over time. Few sex differences between developmentally delayed toddlers. A number of previous studies with fewer than 100 participants each have shown differences between the sexes in autistic toddlers. However, the current study is the largest and most comprehensive of its kind to date, and one of very few studies to assess children with autism at a very early age, according to senior author Karen Pierce, Ph.D., professor of neurosciences and  director of the Autism Center of Excellence at UC San Diego School of Medicine.

“There is no consensus in the field about whether females are more or less impacted than males, and that is probably because there haven't been really large-scale studies at the earliest ages,” said Pierce. “ Based on previous small studies, we had anticipated there would be some sex differences. So we were a little bit surprised to find nothing at all.”

The researchers did, however, find sex differences between typically developing female and male toddlers, with females performing at significantly higher levels than males on more than half of the tests, especially those measuring social skills, language development, and daily living skills.
 
“This is consistent with the literature; female toddlers seem to develop slightly faster than males in terms of their language ability and their social ability and how well they perform daily living skills — adaptive things for a two-year-old,” said Pierce. “Typically developing females are accelerated in their development relative to males.”

Pierce says the findings for autistic children of no clinical differences between males and females at the time of first onset of autism lead to two possible conclusions.

“One is that previous studies that report sex differences are wrong, perhaps due to small sample size, sampling bias, limited study measures, or other methodological issues,” she said. “An alternative conclusion is that sex differences do not exist at the time of first onset, but instead emerge slowly at later ages, driven by psychosocial factors like socialization or differences in biology that may unfold across development.”

To examine this alternative possibility, a high-quality, large-scale study that tracks autistic children from toddlerhood through school age and beyond would be required, according to Pierce.​

Autism is highly heritable, and Pierce says the findings have implications for understanding the development of the condition, enhancing early detection, and improving early intervention. Because the study found that toddlers with autism clustered into scientifically robust subtypes within the autism spectrum rather than by sex, she thinks it may be preferable to focus on these differences instead when seeking to understand clinical heterogeneity and the most appropriate interventions for each subtype, for example.

“If you can improve a toddler's language and communication at the youngest ages possible, then they're going to get their needs met better, and they're going to be able to contribute to society more effectively, because they can do whatever it is that they love to do,” said Pierce. “It's really about having every child reach their full potential.”

Additional authors of the study include first author Sanaz Nazari, second senior author Eric Courchesne, Sara Ramos Cabo, Srinivasa Nalabolu, Cynthia Carter Barnes, Charlene Andreason, Javad Zahiri, Ahtziry Esquivel, Steven J. Arias, Andrea Grzybowski, and Linda Lopez, all at UC San Diego School of Medicine; and Michael V. Lombardo, at Istituto Italiano di Tecnologia.

The study was funded, in part, by National Institutes of Mental Health (grants R01MH118879, R01MH080134, R01MH10446, R01MH121595, P50-MH081755, R01MH110558, R01DC016385).

# # #

END


ELSE PRESS RELEASES FROM THIS DATE:

Enhance agricultural water management in the African Union

2025-05-26
Africa's predominantly rainfed agricultural sector is highly vulnerable to erratic rainfall and the impacts of climate change. Despite having significant irrigation potential, only a small fraction of Africa’s arable land is currently equipped for irrigation. A new policy brief by the United Nations University Institute for Water, Environment and Health (UNU-INWEH) - Implementing the IDAWM Framework to Enhance Agricultural Water Management in the African Union – developed in collaboration with Centre on Climate Change & Planetary Health of London School of Hygiene and Tropical Medicine, International ...

New guideline focused on managing hypertension in primary care

2025-05-26
A new guideline to diagnose and treat hypertension is aimed at helping primary care clinicians, including family physicians, nurses, nurse practitioners, and pharmacists, manage the disease. The new guideline, the first of 2 from Hypertension Canada, is published in CMAJ (Canadian Medical Association Journal) https://www.cmaj.ca/lookup/doi/10.1503/cmaj.241770, and will be republished with permission in Canadian Family Physician and Canadian Pharmacists Journal, with a summary in Canadian Nurse. Hypertension is the most common modifiable risk factor for heart disease and death, affecting about 1 in 4 adults in Canada. Canada has been a ...

New blood test enables the rapid diagnosis of thousands of rare genetic diseases

2025-05-25
Milan, Italy: A new, rapid testing method will greatly help the diagnosis of rare diseases in babies and children, according to research to be presented to the annual conference of the European Society of Human Genetics today (Monday). While rare genetic diseases are uncommon, as their name suggests, there are more than 7,000 types of disease caused by mutations in more than 5,000 known genes, affecting approximately 300 million individuals worldwide. Currently about half of all patients with a suspected rare disease remain undiagnosed and existing testing methods for undiagnosed conditions are typically slow, ...

Genetic investigations reveal reason for severe neuropathy after infection

2025-05-25
Milan, Italy: Neuropathy, a disorder in which damage to nerves can impair sensation and movement, has many causes, including infection1. Now, researchers from the UK have identified distinct genetic changes in a newly-discovered neuropathy and believe that their work will provide insights into the causal mechanism and why some previously healthy people develop neuropathies after infection whereas others do not. Dr Rob Harkness, a postdoctoral research Fellow at the University of Manchester, Manchester, UK, will tell the annual ...

Urban rewilding as a key strategy to combat biodiversity decline

2025-05-25
In recent years, the concept of "rewilding" has risen to prominence in the conservation community, but to date, most efforts have been concentrated on large protected areas far from cities—and consequently, far from urban areas suffering pronounced biodiversity losses. In a recently published BioScience article, Patrick Finnerty (University of Sydney) and colleagues make the case for "urban rewilding" as a vital approach for addressing biodiversity losses, focusing on the rapidly expanding cities that are soon expected to be home to ...

A root development gene that’s older than root development

2025-05-25
A gene that regulates the development of roots in vascular plants is also involved in the organ development of liverworts — land plants so old they don’t even have proper roots. The Kobe University discovery highlights the fundamental evolutionary dynamic of co-opting, evolving a mechanism first and adopting it for a different purpose later. When scientists discover that a gene is necessary for the development of a trait, they are quick to ask since when this gene has been involved in this and how the evolution of the gene has ...

Research reveals missed opportunities to save George Floyd’s life

2025-05-25
The murder of George Floyd could have been avoided if police had responded to the concerns of bystanders reveals research led by Lancaster University. George Floyd was murdered by Minneapolis police officer Derek Chauvin on May 25 2020. For the first time, psychologists have analysed 12 videos recorded on the body-worn cameras of the attending officers, the smartphones of bystanders and local CCTV cameras from 19:55 until 20:42 (CST) on the date of his death. Their research published in American Psychologist examines the range of verbal and physical ...

HKUST discovers novel elastic alloy achieving 20x temperature change and 90% carnot efficiency in solid-state heat pumping

2025-05-25
Researchers at the School of Engineering of the Hong Kong University of Science and Technology (HKUST) have developed a novel elastic alloy called Ti₇₈Nb₂₂, which achieves remarkable efficiency for solid-state heat pumping and exhibits a reversible temperature change (ΔT) ability that is 20 times greater than that of conventional metals when stretched or compressed, offering a promising green alternative to traditional vapor-compression heating and cooling technologies. Nearly half of the world’s energy is consumed for heating, including district heating in the building sector and process heating in various industrial sectors. Currently, global heat ...

Early prediction of preterm birth in cell-free RNA may revolutionize prevention strategies

2025-05-24
Children born before 37 weeks of gestation have a considerably increased risk of dying before they reach the age of five. Predicting the risk of preterm birth (PTB) and hence implementing preventive strategies is complicated by the heterogeneity of the condition, the many unknown mechanisms involved, and the lack of reliable predictive tools. Now, however, researchers have been able to show that blood cell-free RNA (cfRNA) signatures can predict PTB over four months before delivery date, the annual conference of the European Society of Human Genetics will hear ...

Largest phase 3 trial of novel treatment for hypertension shows promising results

2025-05-24
Lorundrostat, a novel therapy which blocks the production of aldosterone from the adrenal glands, demonstrated clinically meaningful and sustained reductions in blood pressure in 1,083 patients with uncontrolled or resistant hypertension, according to the results of a phase 3 trial announced today.  LONDON, UK – 24 May 2025 – The data from the Launch-HTN trial, announced at the 34th European Meeting on Hypertension and Cardiovascular Protection, show that lorundrostat, an aldosterone synthase inhibitor, is ...

LAST 30 PRESS RELEASES:

Liver organoid breakthrough: Generating organ-specific blood vessels

LRA awards 2025 Lupus Insight Prize to Dr. Deepak Rao for uncovering key drivers of immune imbalance in lupus

Terasaki Institute’s Dr. Yangzhi Zhu recognized as 2024 Biosensors Young Investigator Award Recipient

NAU researchers launch open-source robotic exoskeleton to help people walk

Early farmers in the Andes were doing just fine, challenging popular theory

Seeing men as the “default” may be tied to attitudes to politicians, Black people

Risk of crime rises when darkness falls

Data from Poland, Indonesia and Nepal indicate that affectionate behavior is associated with higher relationship satisfaction - though cultural differences impact how affection is displayed and percei

"Boomerang" made from mammoth tusk is likely one of the oldest known in Europe at around 40,000 years old, per analysis of this artifact from a Polish Upper Paleolithic cave

"Shrinking" cod: how humans have altered the genetic make-up of fish

Nitrate in drinking water linked to preterm birth rates

Ancient canoe replica tests Paleolithic migration theory

Eight-month-old babies can adapt their learning style to change

Baby talk – a human superpower?

Molecular-level discovery about heart mechanisms could lead to new heart disease treatments

Study links air pollutant to year-round respiratory health in Jackson

Computational trick enables better understanding of exotic state of matter

Professional responsibility for COVID-19 vaccination in pregnancy

Landmark study uncovers role of tumor microenvironment in nasopharyngeal carcinoma progression which supports personalized treatment

Control of spin qubits at near absolute zero a game changer for quantum computers

Immune cells promoting tumor growth? How dying cancer cells turn their enemies into allies

How diverse brain cells reach a decision together

Pervasive surveillance of people is being used to access, monetize, coerce, and control

New global index aims to help people and nature thrive together

Increased prescribing of ADHD medication and real-world outcomes over time

New study shows how biomass changed over 500 million years

Estimated 2023-2024 COVID-19 vaccine effectiveness in adults

City of Hope’s Dr. Yuman Fong delivers Lister Legacy Lecture, spotlighting surgical cancer innovations

Creation of new molecule could help develop stamp-sized hard drives capable of storing 100 times more data than current tech

COVID vaccine reduces severity of illness, death for adults, especially among at-risk populations

[Press-News.org] No sex differences in autistic toddlers at time of first diagnosis, study finds
A new study from UC San Diego School of Medicine reports no clinical differences in core autism traits between female and male autistic children aged 12-48 months.