This systematic review and meta-analysis examines the association between birth by cesarean delivery and risk of neurodevelopmental and psychiatric disorders in the offspring compared with birth by vaginal delivery.

Background. Social anxiety disorder (SAD) has been linked to academic underachievement, but previous studies had methodological limitations. We investigated the association between SAD and objective indicators of educational performance, controlling for a number of covariates and unmeasured confounders shared between siblings. Methods. This population-based birth cohort study included 2 238 837 individuals born in Sweden between 1973 and 1997, followed-up until 2013. Within the cohort, 15 755 individuals had a recorded ICD-10 diagnosis of SAD in the Swedish National Patient Register. Logistic regression models tested the association between SAD and educational performance. We also identified 6488 families with full siblings discordant for SAD. Results. Compared to unexposed individuals, individuals diagnosed with SAD were less likely to pass all subjects in the last year of compulsory education [adjusted odds ratios (aOR) ranging from 0.19 to 0.44] and less likely to be eligible for a vocational or academic programme in upper secondary education [aOR = 0.31 (95% confidence interval [CI] 0.30-0.33) and aOR = 0.52 (95% CI 0.50-0.55), respectively], finish upper secondary education [aOR = 0.19 (95% CI 0.19-0.20)], start a university degree [aOR = 0.47 (95% CI 0.45-0.49)], obtain a university degree [aOR = 0.35 (95% CI 0.33-0.37)], and finish postgraduate education [aOR = 0.58 (95% CI 0.43-0.80)]. Results were attenuated but remained statistically significant in adjusted sibling comparison models. When psychiatric comorbidities were taken into account, the results were largely unchanged. Conclusions. Treatment-seeking individuals with SAD have substantially impaired academic performance throughout the formative years. Early detection and intervention are warranted to minimise the long-term socioeconomic impact of the disorder.