Fig. 4

Adjusted odds ratios and two-sided 95% confidence intervals of Autism Spectrum Disorder (ASD) following cesarean section (CS) compared with vaginal delivery (VD) for further analysis of past miscarriage history. The left and right present the results of analysis with and without a history of miscarriage, respectively. a Forest plots of the association between CS and ASD in study samples with and without a history of miscarriage. The analysis was further classified based on methods of anesthesia (RA vs. GA) and different surgery indication subgroups (emergency CS, voluntary CS and indicated CS), presented in b and c, respectively. Gray dashed horizontal lines separate the results of different stratification analyses. Each adjusted odds ratio was estimated from logistic regression after adjusting for confounding factors (parity number, gestational diabetes, infant’s weight and children’s sex, and age)