Autism & Developmental

Pre- and perinatal factors in high-functioning females and males with autism.

Lord et al. (1991) · Journal of autism and developmental disorders 1991
★ The Verdict

Birth complications add only a tiny amount of risk for high-functioning autism.

✓ Read this if BCBAs who work with bright autistic teens or adults.
✗ Skip if Clinicians serving mostly non-verbal or medically complex kids.

01Research in Context

01

What this study did

Duker et al. (1991) looked at birth records of 30 high-functioning autistic adults.

They scored how many pregnancy or delivery problems each person had.

Then they compared the scores to those of the adults’ own brothers and sisters.

02

What they found

The autistic group had only slightly higher problem scores.

Most of that small gap came from being later-born in the family, not from true birth stress.

The authors say pre-birth events matter little for this bright subgroup.

03

How this fits with other research

Hwang et al. (2013) tracked every child born in Taiwan and saw a 2–4× jump in autism after very early birth.

Their big sample shows preterm risk is real, but the 1991 study simply did not include many very early births.

Tioleco et al. (2021) pooled 36 studies and found a small, solid link between maternal infection during pregnancy and later autism.

The meta-analysis adds newer data, yet still agrees the effect size is modest—exactly what the 1991 paper called “minor.”

04

Why it matters

If you assess high-functioning clients, do not over-weight birth history.

Focus energy on current skill building, not on past events the client cannot change.

When families ask about causes, you can say birth issues play only a bit part in bright autistic profiles.

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Drop birth-history questions from your intake form for high-functioning clients and spend the saved time on strengths-based goal setting.

02At a glance

Intervention
not applicable
Design
other
Sample size
100
Population
autism spectrum disorder
Finding
positive
Magnitude
small

03Original abstract

Pregnancy and delivery complications as indicated in medical records and maternal reports for 23 high-functioning autistic females and 23 high-functioning males of similar IQ and age were compared with those of 54 of their normally developing siblings. Autistic subjects of both sexes had higher non-optimality scores than their siblings. Much of this difference was accounted for by a higher incidence of firstborns and fourth- or later-borns in the autistic group. Of factors found in previous research with mentally handicapped, autistic samples, only estimated weeks of gestation greater than 42 occurred more often in autistic subjects than siblings. The only sex difference specific to the autistic group was that autistic males came from larger families than females. These data provide slight support for the contribution of nonspecific pre- and perinatal factors to other etiological bases of autism. It is proposed that pre- and perinatal factors may play less of a role in autism in high-functioning individuals than suggested in studies of autism associated with severe retardation.

Journal of autism and developmental disorders, 1991 · doi:10.1007/BF02284760