IDF Diabetes Atlas: The prevalence of pre-existing diabetes in pregnancy - A systematic reviewand meta-analysis of studies published during 2010-2020.

Objectives: To estimate the prevalence of pre-existing diabetes in pregnancy from studies published during 2010-2020.

Methods: We searched PubMed, CINAHL, Scopus and other sources for relevant data sources. The prevalence of overall pre-existing, type 1 and type 2 diabetes, by country, region and period of study was synthesised from included studies using the inverse-variance heterogeneity model and the Freeman-Tukey transformation. Heterogeneity was assessed using the I statistic and publication bias using funnel plots.

Results: We identified 2479 records, of which 42 data sources with a total of 78 943 376 women, met the eligibility criteria. The included studies were from 17 countries in North America, Europe, the Middle East and North Africa, Australasia, Asia and Africa. The lowest prevalence was in Europe (0.5%, 95 %CI 0.4-0.7) and the highest in the Middle East and North Africa (2.4%, 95 %CI 1.5-3.1). The prevalence of pre-existing diabetes doubled from 0.5% (95 %CI 0.1-1.0) to 1.0% (95 %CI 0.6-1.5) during the period 1990-2020. The pooled prevalences of pre-existing type 1 and type 2 diabetes were 0.3% (95 %CI 0.2-0.4) and 0.2% (95 %CI 0.0-0.9) respectively.

Conclusion: While the prevalence of pre-existing diabetes in pregnancy is low, it has doubled from 1990 to 2020.