We conducted logistic regression analyses to evaluate the relationship between maternal age and child health. We first estimated the crude odds ratios (ORs) and 95% confidence intervals (95% CIs) linking the maternal age groups with each health outcome [Unadjusted Model]. We re-calculated the ORs and 95% CIs controlling for potential confounders [Adjusted Model]. In the follow-up analyses, we added preterm births and birthweight to the list of factors included in the adjusted Model [Mediator-adjusted Model]. We also tested whether the associations between maternal age and child health outcomes were linear. In the follow-up analyses, we divided the sample into parity 1 and parity 2 and analyzed the sub-samples using the same models we used in the main analyses. The youngest maternal age group (i.e., <25) served as the reference group, and we conducted our analyses with complete cases. All statistical analyses were performed with Stata (Version 13/SE, STATA Corp., Texas, USA).