Fig. 3. Associations between key early-life factors and emotional problems at ages 2 and 4 years, mediated by OS biomarker 8-OHGua at 36 weeks.

^*Prenatal factors. Maternal education (lower indicates no university degree). Residential SED represents greater disadvantage. Minimally adjusted for child’s sex, gestational age at urine collection, and child’s age at the time of behavioural assessment. 8-OHGua 8-hydroxyguanosine, CBCL Child Behavior Checklist, DSM-5 Diagnostic and Statistical Manual of Mental Disorders Version 5, M maternal, SED socioeconomic disadvantage, OS oxidative stress, SDQ Strengths and Difficulties Questionnaire, SHS secondhand smoke.