In a groundbreaking finding that could reshape the way autism is diagnosed in young children, an international research team has discovered that, in toddlerhood, autism presents nearly identically among girls and boys. This revelation, published recently in Nature Human Behaviour and reported by Science News, challenges longstanding beliefs and provides hope for more accurate and inclusive early interventions.
The significance of this discovery lies in its potential to reduce gender-based disparities in autism diagnosis and treatment. Autism spectrum disorder (ASD) has historically been seen as affecting boys far more frequently—roughly four times as often as girls, according to global statistics (Science News). However, previous studies left uncertainty about whether the symptoms truly differ according to sex, or whether diagnostic criteria—often based on observations in boys—have contributed to underdiagnosis among girls.
The latest study, the largest of its kind, examined 2,618 children with autism between the ages of 1 and 4, addressing limitations—from small samples to the confounding effects of older children’s life experiences—that plagued earlier research. Lead author, a neuroscientist and co-director of the University of California, San Diego’s Autism Center of Excellence, revealed that girls and boys were virtually indistinguishable on nearly all 18 measures assessed, including eye-tracking attention tests, language skills, and the ability to dress or feed oneself.
“We were actually incredibly surprised to find that there were no differences, no matter where, no matter how we looked,” the lead researcher told Science News. Beyond the scientific surprise, this consistency across measures is expected to impact how clinicians approach early diagnosis and intervention, making it less likely that girls with ASD will be overlooked due to outdated assumptions.
One minor exception did emerge: parents of girls with autism reported that their daughters performed slightly better with daily living skills like feeding themselves. However, professionals analyzing the results say this difference is too small to have clinical significance; it may reflect subtle normative gender variations that also appear in children without autism.
The study also compared development generally among non-autistic children, confirming that girls in early childhood typically score slightly better on certain social and developmental indices than boys. But for children with autism, these gaps vanished. “At this very young age, they’re just not presenting differently from a diagnostic perspective. They’re just not,” said the principal investigator.
These findings hold major implications for Thailand, where awareness and understanding of autism are increasing, but both families and health professionals still struggle with late or missed diagnoses in girls. While the Ministry of Public Health has made advances—such as including ASD screening in standard pediatric check-ups and running awareness campaigns—social stigma and lingering misconceptions persist. The new research suggests it is not sufficient to rely on stereotypes of “male” autism traits, especially when seeking to identify girls who could benefit from early support (Nature Human Behaviour).
A leading developmental scientist and autism expert at Boston University, commenting on the findings, explained, “This study, with its large sample size, provides stronger evidence for there being no differences in how autism is expressed in girls and boys.” This calls for increased vigilance among parents, teachers, and Thai pediatricians: if early symptoms are nearly indistinguishable, vigilance in both sexes is needed, rather than selective awareness based on gender.
However, some experts urge caution, noting limitations to the study’s screening methods. Because these relied on established diagnostic tools, some girls with milder autism may not have been identified and thus were underrepresented in the data. “Girls with milder symptoms may not have been identified on the screener,” a senior autism expert told Science News, suggesting that while the study reflects existing diagnoses, it may still miss subtle differences that emerge with broader or more sensitive screening—something Thai health authorities may need to consider.
In the Thai context, cultural norms can further obscure autism traits in girls. Young girls in Thailand may be socialized to be quiet and obedient, behaviors that sometimes mask or overlap with early autism signs such as limited communication or social interaction. Caregivers, especially outside urban centers, may see autistic behaviors as shyness or timidity rather than cause for assessment and support. Consequently, autism is often diagnosed in girls at older ages, when symptoms become too disruptive for school or family harmony (Bangkok Post).
The question remains: Do gender differences in autistic traits emerge later in childhood, or are some girls simply missed by current diagnostic tools? The research team plans to follow these children as they grow, hoping to shed light on when, why, and how—and whether—differences eventually appear. If confirmed, this could inform not only medical screening but also educational accommodations and social support programs in schools, where Thai girls with high functioning ASD are sometimes lost in the system.
Experts agree that further research is crucial for understanding why girls are less frequently identified at young ages, despite similar early symptoms, and whether educational or biological factors account for any later divergence. Over the long term, results could reshape global autism statistics, currently dominated by male diagnostic trends, and could also inform more equitable policymaking and funding for support services in Thailand and other countries (Autism Research Asia).
Meanwhile, the practical takeaway for Thai families, teachers, and doctors is clear: Early signs of autism—such as delayed speech, limited eye contact, repetitive behaviors, or challenges in social play—should prompt evaluation in both boys and girls. Gender-based assumptions are increasingly unsupported by scientific evidence, and early intervention remains the single most effective way to improve outcomes, regardless of sex. Pediatricians and parents are urged to consult with child development specialists at the earliest signs of concern and to advocate for thorough assessment if girls display traits that could be attributed to ASD.
For educators, this study underscores the importance of inclusive classroom strategies, individualized learning plans, and continued professional development on neurodiversity. Simple steps—such as flexible routines, visual aids, and positive behavioral supports—help children with differing social and learning needs, while comprehensive teacher training programs like those piloted by the Thai Ministry of Education are crucial for building understanding and reducing stigma (UNICEF Thailand Education).
In the broader community, supporting local autism advocacy groups and attending public awareness seminars can help dispel myths and encourage more families to seek assessment and support. Thailand’s growing network of autism resource centers and therapist networks makes early intervention increasingly accessible even outside Bangkok (Autism Thailand).
In conclusion, as this latest research demonstrates, autism in toddlers seems to transcend gender, at least in its earliest stages. For Thai readers, the essential message is to look beyond stereotypes, remain attentive to all children’s development, and advocate for early, equitable support regardless of gender. Together, by deepening understanding and challenging old assumptions, we can help ensure that no child with autism—girl or boy—is left behind.
Sources: Science News, Nature Human Behaviour, Bangkok Post, Autism Research Asia, UNICEF Thailand Education, Autism Thailand