Strengths and limitations
There are several strengths in this study. First, the basis for research selection was explicit search strategies and well-defined research inclusion criteria. Grey literature was examined, and articles in different languages were included. Second\soutly, there is currently no systematic review of studies focusing on the impact of gestational diabetes on multiple types of children’s allergic diseases. In addition, this study conducted a subgroup analysis on the types of epidemiological studies and explored the research effectiveness of different types of epidemiological studies.
There are also some limitations in our study. All the available evidence was derived from observational studies (cohort, cross-sectional, case–control), which have an inherent bias. In addition, not all studies provided information on preterm/term births, therefore, the confounder may arise from preterm/term status.