Narrowly versus broadly defined autism spectrum disorders: differences in pre- and perinatal risk factors.
Smoking during pregnancy raises the odds of PDD-NOS and lowers IQ in that group.
01Research in Context
What this study did
The team looked at the kids with ASD. They split them into two groups: classic autistic disorder and the broader PDD-NOS group.
They checked birth records and mom interviews for smoking, infections, stress, and birth problems.
What they found
Smoking during pregnancy showed up more in the PDD-NOS group. These kids also scored lower on IQ tests. Classic autism had more firstborn kids and birth complications.
How this fits with other research
Li et al. (2016) found that obese moms also raise autism risk. Together with Peters et al. (2013), the pattern is clear: what happens in the womb matters.
McConkey et al. (2010) showed that low birth weight and pre-eclampsia raise ASD odds. Peters et al. (2013) adds smoking to that same risk list.
Che et al. (2025) flips the coin: moms who ate a Mediterranean diet had kids with better social skills. The takeaway is that both harmful and helpful prenatal factors shape later outcomes.
Why it matters
When you meet a new client, ask about mom's smoking during pregnancy. If the child has PDD-NOS and lower IQ, this may be part of the story. Use this info to build empathy with families and to target early language and cognitive goals.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Add one question to your intake form: 'Did mom smoke during pregnancy?' Note the answer in your assessment summary.
02At a glance
03Original abstract
This study examined the differential contribution of pre- and perinatal risks in narrowly versus broadly defined autism spectrum disorder (ASD) and across core symptom domains, IQ and co-morbid problems. Children with a DSM-IV diagnosis of autistic disorder (AD) (n = 121) or pervasive developmental disorder not otherwise specified (PDD-NOS) (n = 75) were compared to a typical control sample (n = 311). Diagnoses were based on extensive assessments between 12 and 49 months of age (M = 33.3, SD = 6.4) and re-evaluated at 43-98 months (M = 68.1, SD = 10.7) in 70% of the cases. Compared with controls, cases with ASD were more likely to be firstborn and show a suboptimal condition after birth. Case mothers reported more infections and more stress during pregnancy. Although the ASD subgroups showed mostly overlapping risks, cases with PDD-NOS differed from those with AD by higher exposure to smoking during pregnancy (SDP) and by a negative association of smoking with IQ, regardless of confounders. SDP appears to contribute more to broadly defined (PDD-NOS) than to narrowly defined ASD (AD). Findings suggest differences in etiological contributors between ASD phenotypes.
Journal of autism and developmental disorders, 2013 · doi:10.1007/s10803-012-1678-6