Prevalence of Gestational Diabetes in Iran: A Systematic Review and Meta-analysis

Gestational diabetes mellitus (GDM) is the most common complication of pregnancy and an important public health concern. Several studies have investigated the prevalence of gestational diabetes in different parts of Iran with different results.

The present study aimed to review studies on gestational diabetes prevalence and estimate the prevalence of gestational diabetes in Iran.

A search on gestational diabetes mellitus and related synonyms was conducted using global and national databases, including PubMed, Science Direct, Scopus, Web of Sciences, Google Scholar, SID, IranMedex, Magiran, Irandoc, Medlib. Moreover, gray literature and reference checks and a library search were conducted. Keywords included: prevalence, Iran, gestational diabetes mellitus (GDM), and their synonyms. The inclusion criteria were observational studies (cross-sectional, prospective cohorts, and retrospective cohorts) published in Persian or English between 2000 and 2020 on the prevalence or incidence of gestational diabetes in Iran, a sample size of more than 100 people, and availably of full texts. The selected articles were thoroughly reviewed, and after quality assessment, the required information was extracted and included in the meta-analysis.

From 907 articles, 48 were included in the meta-analysis according to the inclusion criteria, which included 51,259 patients with an average age (standard deviation) of 27.05 years (1.83). The overall prevalence of GDM in Iran was 10% (11,9: 95% confidence interval). The prevalence of GDM had increased in recent years, from 4% before 2005 to 16% in 2016 to 2020 (20,12: 95% CI). There was significant heterogeneity between studies, and the I-square index was 98%.

The prevalence of gestational diabetes in Iran is slowly increasing. The increasing prevalence of gestational diabetes can seriously threaten the health of mothers, fetuses, and newborns in the near future.