Post-Traumatic Stress Symptoms in Parents of Preschoolers First Diagnosed with Autism: Gender Differences and Correlations with Broad Autism Phenotypes

(1) Background: A child's new diagnosis of autism can represent a highly stressful event for parents. Subthreshold autistic traits (ATs) have been linked to higher vulnerability to psychopathology when exposed to stressful situations, and high rates of ATs have been reported among parents of autistic children. This study aimed to evaluate post-traumatic stress spectrum symptoms (PTSS) in parents of preschool children newly diagnosed with autism and to explore differences between mothers and fathers, besides the correlations with ATs. (2) Methods: A total of 134 parents of children newly diagnosed with autism were assessed by trained psychiatrists from the University of Pisa using the Autism Spectrum Quotient (AQ), the Adult Autism Subthreshold Spectrum-Self Report (AdAS-SR), the Trauma and Loss Spectrum-Self Report (TALS-SR), and the Social and Occupational Functioning Assessment Scale (SOFAS). (3) Results: Approximately 10% of parents met DSM-5-TR criteria for symptomatologic PTSD, with nearly 40% experiencing partial PTSD symptoms related to their child's diagnosis. Mothers showed higher PTSD rates than fathers. The ATs significantly correlated with elevated TALS-SR scores, and logistic regression revealed a positive association between ATs and PTSD (<i>p</i> < 0.001). Linear regression analysis indicated that higher TALS-SR scores predicted lower SOFAS scores (<i>p</i> = 0.004). (4) Conclusions: These findings highlight the potential traumatic impact of a child's new autism diagnosis on parents, particularly mothers and individuals with ATs. The results underscore the importance of targeted support strategies for parents, considering their key role in early interventions. Further research is needed to better understand parental psychological responses and to enhance support systems, ultimately improving family wellbeing and child outcomes.