Prenatal fever and autism risk.

Area of Science:

• Neurodevelopmental Disorders
• Infectious Disease Epidemiology
• Reproductive Health

Background:

• Prenatal infections are suspected to increase the risk of autism spectrum disorders (ASDs).
• Fever is a common indicator of infection during pregnancy.

Purpose of the Study:

• To investigate the association between maternal fever during pregnancy and the risk of ASDs in offspring.
• To determine if fever in specific trimesters or frequency of fever episodes influences ASD risk.

Main Methods:

• Prospective cohort study in Norway.
• Maternal fever exposure data collected via questionnaires.
• ASD case status determined through clinical assessments and registry linkages.
• Logistic regression analysis used to assess associations.

Main Results:

• Maternal fever in the second trimester was significantly associated with increased ASD risk (aOR, 1.40).
• Risk of ASD increased with the number of fever episodes after 12 weeks' gestation (aOR, 3.12 for ≥3 episodes).
• A dose-dependent relationship was observed between maternal fever exposure and ASD risk.

Conclusions:

• Gestational maternal fever, particularly in the second trimester, is associated with an elevated risk of ASDs.
• The findings suggest a role for maternal infection and immune responses in the pathogenesis of some ASD cases.
• Further research into the mechanisms linking maternal infection to ASD development is warranted.