Sex differences in autism spectrum disorder: an examination of developmental functioning, autistic symptoms, and coexisting behavior problems in toddlers.
Toddler girls with ASD show softer signs—sleep trouble and communication gaps—while boys wave bigger repetitive flags.
01Research in Context
What this study did
Matson et al. (2009) watched toddlers with autism. They wanted to know if boys and girls act the same.
They checked talking skills, play routines, sleep, and tantrums. The team wrote down every difference they saw.
What they found
Girls spoke a little less and woke more at night. Boys flapped, lined toys, and stared at fans more often.
Overall, the two groups looked alike. The small sex gaps are easy to miss if you only count total autism scores.
How this fits with other research
Ros-Demarize et al. (2020) found the same girl-communication gap eleven years later. The pattern holds.
Matheis et al. (2019) seem to disagree. When they matched toddlers for IQ, girls talked better than boys. The fight disappears once you control for smarts.
Kocher et al. (2015) saw zero sex differences in a big sample. Their null result warns us that the gaps are tiny and may not show up in every clinic.
Why it matters
Watch girls who sleep poorly or cling to caregivers. These quiet signs can point to autism even when eye contact looks fine. Watch boys who line toys or quote scripts. Use sex-tuned red flags, not just the total score, when you decide to refer for an evaluation.
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02At a glance
03Original abstract
Little is known about the female presentation of autism spectrum disorder (ASD) during early childhood. We investigated sex differences in developmental profiles using the Mullen Scales of Early Learning, autistic symptoms on the ADOS-G, and coexisting behavior problems on the CBCL in 157 boys and 42 girls with ASD aged 1.5-3.9 years. Overall, boys and girls evidenced a markedly similar pattern of developmental profiles, autism symptoms, and coexisting behavior problems, although subtle differences exist. Boys and girls evidenced a similar pattern of developmental strengths and weaknesses. Girls with ASD evidenced greater communication deficits than boys and boys evidenced more restricted, repetitive, and stereotyped behavior than girls. Girls exhibited more sleep problems and anxious or depressed affect than boys.
Journal of autism and developmental disorders, 2009 · doi:10.1007/s10803-009-0810-8