Account

Progression to type 2 diabetes in women with a known history of gestational diabetes: systematic review and meta-analysis

Vounzoulaki E, Khunti K, Abner SC, Tan BK, Davies MJ, Gillies CL

Published May 13, 2020 BMJ
DOI 10.1136/bmj.m1361 PMID 32404325 PMC PMC7218708

RRM Academy Synopsis

Gestational diabetes is linked to nearly 10-fold type 2 diabetes risk

A meta-analysis of 20 observational studies found that type 2 diabetes risk was almost 10 times higher after gestational diabetes than after a pregnancy with normal blood sugar. The studies included 67 956 women with gestational diabetes and 1 264 417 controls. Follow-up lasted one to 25 years.

Key Findings

  • The pooled relative risk of type 2 diabetes was 9.51 (95% confidence interval 7.14 to 12.67) in women with previous gestational diabetes versus controls, across 20 studies.
  • Every included study found a higher risk of type 2 diabetes in women with gestational diabetes than in controls.
  • In studies of white populations, cumulative incidence after gestational diabetes was 9.91% (9.39% to 10.42%), versus 16.46% (16.16% to 16.77%) in mixed and 15.58% (13.30% to 17.86%) in predominantly non-white ones.
  • Among women with gestational diabetes, pooled cumulative incidence reached 9.22% (7.19% to 11.26%) in studies of one to five years and 16.15% (15.83% to 16.47%) in studies of over 10 years.
  • Results varied widely between studies (I2=96.5%). Differences between ethnicity subgroups were not statistically significant (white v mixed, P=0.26; white v non-white, P=0.54).

Interpretation

The review pooled 20 observational studies. The result suggests an association between gestational diabetes and type 2 diabetes diagnosed at least 12 months after pregnancy. Most studies had a low risk of bias, and tests found no sign of publication bias. Results varied widely, and the authors could not identify the main sources of that variation. Only English-language reports were included, and ethnicity was grouped into broad categories. The authors found it difficult to reach conclusions about when type 2 diabetes began from study-level data.

RRM Context

Restorative reproductive medicine treats a pregnancy complication as a clue to how the body works. Here, women with gestational diabetes developed type 2 diabetes more often than controls over one to 25 years of follow-up. That history belongs in a cause-based review of reproductive health.

Our editorial summary of this paper, not the article's abstract.

Abstract

Objective

To estimate and compare progression rates to type 2 diabetes mellitus (T2DM) in women with gestational diabetes mellitus (GDM) and healthy controls.

Design

Systematic review and meta-analysis.

Data Sources

Medline and Embase between January 2000 and December 2019, studies published in English and conducted on humans.

Study Eligibility Criteria

Observational studies investigating progression to T2DM. Inclusion criteria were postpartum follow-up for at least 12 months, incident physician based diagnosis of diabetes, T2DM reported as a separate outcome rather than combined with impaired fasting glucose or impaired glucose tolerance, and studies with both a group of patients with GDM and a control group.

Results

This meta-analysis of 20 studies assessed a total of 1 332 373 individuals (67 956 women with GDM and 1 264 417 controls). Data were pooled by random effects meta-analysis models, and heterogeneity was assessed by use of the I2 statistic. The pooled relative risk for the incidence of T2DM between participants with GDM and controls was estimated. Reasons for heterogeneity between studies were investigated by prespecified subgroup and meta-regression analyses. Publication bias was assessed by funnel plots and, overall, studies were deemed to have a low risk of bias (P=0.58 and P=0.90). The overall relative risk for T2DM was almost 10 times higher in women with previous GDM than in healthy controls (9.51, 95% confidence interval 7.14 to 12.67, P<0.001). In populations of women with previous GDM, the cumulative incidence of T2DM was 16.46% (95% confidence interval 16.16% to 16.77%) in women of mixed ethnicity, 15.58% (13.30% to 17.86%) in a predominantly non-white population, and 9.91% (9.39% to 10.42%) in a white population. These differences were not statistically significant between subgroups (white v mixed populations, P=0.26; white v non-white populations, P=0.54). Meta-regression analyses showed that the study effect size was not significantly associated with mean study age, body mass index, publication year, and length of follow-up.

Conclusions

Women with a history of GDM appear to have a nearly 10-fold higher risk of developing T2DM than those with a normoglycaemic pregnancy. The magnitude of this risk highlights the importance of intervening to prevent the onset of T2DM, particularly in the early years after pregnancy.

Systematic Review Registration

PROSPERO CRD42019123079.

By this author

Related research

Elpida Vounzoulaki, Kamlesh Khunti, Sophia C Abner, Bee K Tan, Melanie J Davies, Clare L Gillies
E Vounzoulaki, K Khunti, S Abner, B Tan, M Davies, C Gillies
PMID 32404325 32404325 DOI 10.1136/bmj.m1361 10.1136/bmj.m1361 Vounzoulaki et al. 2020, Vounzoulaki 2020

Learn

Resources

Tools

Help

Candid Platinum Transparency 2026

RRM Academy is a 501(c)(3) nonprofit providing free and low-cost education in restorative reproductive medicine for patients and healthcare professionals.

This site is an educational resource and does not provide medical advice. Inclusion of a study does not imply endorsement of its findings. Always consult a qualified healthcare provider for diagnosis and treatment.

© 2026 RRM Academy · All Rights Reserved

Restorative Reproductive Medicine Foundation · 3401 Hartzdale Dr, Ste 103B PMB 3518, Camp Hill, PA 17011 · EIN: 93-4594315
Sitemap AI Instructions Developers Terms of Use Medical Disclaimer Privacy Policy