Date of Conferral



Doctor of Public Health (DrPH)


Public Health


Angela W. Prehn


Autism spectrum disorders (ASD) constitute life-long neurodevelopmental conditions. Globally, ASD risk for males remains 2 to 4 times greater than for females. Critical exposure mechanisms, their timing on ASD risk, and associations with the ASD gender differential remain elusive. The purpose of this study was to describe the relationship between preconception, pregnancy, recalled lactation practice, and infant traits, on ASD risk and the gender differential of ASD. A recently published temporal framework was adapted to study effects of maternal smoking and vitamin use, and recalled lactation practice on offspring ASD diagnosis with adjustment for preconception health and infant breathing traits. A retrospective case-control analysis using 733 child data records from U.S. autism registry characterized child gender-stratified relationships of 9 study variables. Logistic regression results showed prior maternal smoking, male gender, and maternal recollection of lactation practices were associated with offspring ASD diagnosis. Exposure factors associated with ASD did not differ by child gender or maternal vitamin use. Infant respiratory distress at birth was a covariate and collinearly related to obstetric risks. Maternal smoking was antecedent to respiratory distress and lactation practice. Study limitations included incomplete responses without repeated measures for recalled lactation practice and maternal diet variables. The implications for positive social change include a better understanding of reproductive, preconception, and prenatal risk factors of ASD. The study results have implications for reproductive health, smoking cessation programs, family planning, and prenatal care for women of reproductive age.