Meta Analysis

Diabetologia

, Volume 51, Issue 5, pp 726-735

First online:

Caesarean section is associated with an increased risk of childhood-onset type 1 diabetes mellitus: a meta-analysis of observational studies

  • C. R. CardwellAffiliated withDepartment of Epidemiology and Public Health, School of Medicine and Dentistry, Queen’s University Belfast Email author 
  • , L. C. SteneAffiliated withDivision of Epidemiology, Norwegian Institute of Public HealthDiabetes Research Centre, Aker and Ullevål University Hospitals
  • , G. JonerAffiliated withDiabetes Research Centre, Aker and Ullevål University HospitalsFaculty of Medicine, University of Oslo
  • , O. CinekAffiliated withSecond Medical School, Charles University
  • , J. SvenssonAffiliated withSteno Diabetes Centre
  • , M. J. GoldacreAffiliated withDepartment of Public Health, Oxford University
  • , R. C. ParslowAffiliated withPaediatric Epidemiology Group, University of Leeds
  • , P. PozzilliAffiliated withUniversity Campus Bio-Medico
  • , G. BrigisAffiliated withDepartment of Public Health and Epidemiology, Riga Stradins University
    • , D. StoyanovAffiliated withChildren’s Diabetic Centre
    • , B. UrbonaitėAffiliated withInstitute of Endocrinology, Kaunas University of Medicine
    • , S. ŠipetićAffiliated withInstitute of Epidemiology, School of Medicine, Belgrade University
    • , E. SchoberAffiliated withDepartment of Paediatrics, Medical University of Vienna
    • , C. Ionescu-TirgovisteAffiliated withNutrition and Metabolic Diseases Clinic, ‘N. Paulescu’ Institute of Diabetes
    • , G. DevotiAffiliated withDepartment of Social Sciences and Communication, University of Lecce
    • , C. E. de BeaufortAffiliated withClinique Pédiatrique Luxembourg
    • , K. BuschardAffiliated withBartholin Institutett, Rigshospitalet
    • , C. C. PattersonAffiliated withDepartment of Epidemiology and Public Health, School of Medicine and Dentistry, Queen’s University Belfast

Abstract

Aims/hypothesis

The aim of this study was to investigate the evidence of an increased risk of childhood-onset type 1 diabetes in children born by Caesarean section by systematically reviewing the published literature and performing a meta-analysis with adjustment for recognised confounders.

Methods

After MEDLINE, Web of Science and EMBASE searches, crude ORs and 95% CIs for type 1 diabetes in children born by Caesarean section were calculated from the data reported in each study. Authors were contacted to facilitate adjustments for potential confounders, either by supplying raw data or calculating adjusted estimates. Meta-analysis techniques were then used to derive combined ORs and to investigate heterogeneity between studies.

Results

Twenty studies were identified. Overall, there was a significant increase in the risk of type 1 diabetes in children born by Caesarean section (OR 1.23, 95% CI 1.15–1.32, p < 0.001). There was little evidence of heterogeneity between studies (p = 0.54). Seventeen authors provided raw data or adjusted estimates to facilitate adjustments for potential confounders. In these studies, there was evidence of an increase in diabetes risk with greater birthweight, shorter gestation and greater maternal age. The increased risk of type 1 diabetes after Caesarean section was little altered after adjustment for gestational age, birth weight, maternal age, birth order, breast-feeding and maternal diabetes (adjusted OR 1.19, 95% CI 1.04–1.36, p = 0.01).

Conclusions/interpretation

This analysis demonstrates a 20% increase in the risk of childhood-onset type 1 diabetes after Caesarean section delivery that cannot be explained by known confounders.

Keywords

Caesarean section Cesarean section Diabetes mellitus Epidemiology Type 1