Maternal Exposure to Childhood Abuse, Mate Selection, and Autism Spectrum Disorder in Offspring

Background:  Maternal experience of childhood abuse is associated with offspring ASD, but mechanisms are unknown. Biological effects of abuse are one possibility, and genetics is another. Prior research indicates that girls with autistic traits may be targeted for childhood abuse, inducing an association between maternal genetics and maternal experience of childhood abuse.  Additionally, women who experienced abuse in childhood may select as mates men with high levels of autistic traits, and paternal autistic traits predispose to ASD in offspring. Experience of childhood abuse may be an indicator of genetic risk for ASD.

Objectives:  

To examine possible reasons for the association between childhood abuse and ASD by addressing three questions: 1) Are women who experienced childhood abuse more likely to select mates with high levels of autistic traits?  2) If so, is this association independent of women’s own autistic traits?  3) Is the association of maternal abuse and offspring ASD explained by parents’ autistic traits?

Methods:  A nested case-control study in the Nurses' Health Study II (N= 222 cases, N=854 controls). ASD based on maternal report, validated with the Autism Diagnostic Interview-Revised in a subset. Parental autistic traits assessed with the Social Responsiveness Scale (SRS). Odds ratios (OR) and 95% confidence intervals (CI) of paternal high autistic traits and ASD estimated with logistic regression.

Results:  

Maternal childhood abuse was strongly associated with high paternal autistic traits (severe sexual abuse, OR=3.98, 95% CI=1.29, 12.27; severe physical/emotional abuse, OR=2.24, 95% CI=1.30, 3.88). Maternal childhood abuse predicted offspring ASD (severe combined abuse, RR=3.62, 95% CI=1.80, 7.28). Paternal autistic traits accounted for 21% of the association between maternal childhood abuse and offspring risk of ASD (adjusted RR=2.97, 95% CI=1.45, 6.09).

Conclusions:

Childhood abuse may affect women’s mate selection. At the same time, parental autistic traits alone do not account for the association of maternal childhood abuse with offspring ASD, as these explained only a small portion of the association of maternal abuse with offspring ASD.