Secular trend in prevalence and socioeconomic correlates of diabetes in pregnancy in Taiwan

Objective: To assess the trend in prevalence and socioeconomic correlates of diabetes in pregnancy (DIP) in Taiwan from 2007 to 2014. Methods: In all, 1 606 344 pregnancies, including 199 383 DIP (1693 with pre-pregnancy type 1 diabetes [T1DM], 17 171 with pre-pregnancy type 2 diabetes [T2DM], and 180 519 with gestational diabetes mellitus [GDM]) were investigated. Logistic regression models were performed to identify the covariates significantly associating with DIP. Results: Over the study period, the prevalence of pre-pregnancy T2DM increased by 568.44%; the prevalence of T1DM and GDM also increased but with a smaller magnitude. However, only the prevalence of pre-pregnancy T2DM showed an increase after socioeconomic variables were considered. Compared with immigrant mothers, native-born mothers had a significantly higher adjusted odds ratio of DIP, particularly pre-pregnancy T1DM (3.33, 95% confidence interval 1.57–7.05). Additionally, indigenous mothers and those from rural areas had a higher prevalence of pre-pregnancy T2DM but lower prevalence of GDM. Lower maternal education and income were associated with higher prevalence of pre-pregnancy T1DM but lower prevalence of pre-pregnancy T2DM and GDM. Conclusion: Socioeconomic variables largely accounted for the increased secular trend in pre-pregnancy T1DM and GDM, but the prevalence of pre-pregnancy T2DM still doubled, which was independent of socioeconomic covariates.