A Systematic Review and Meta-Analysis of Diabetes During Pregnancy and Congenital Genitourinary Abnormalities

INTRODUCTION: This study aimed to assess available epidemiological evidence of the relationship between diabetes during pregnancy and congenital abnormalities of the kidney and the urinary tract (CAKUT). METHODS: POPLINE, MEDLINE, EMBASE, Global Health, CINAHL, and Cochrane Library were searched to retrieve 6962 articles of which 15 case-control and 11 cohort studies met the inclusion criteria. Random-effects meta-analysis was performed to estimate the association between CAKUT and diabetes during pregnancy. RESULTS: Offspring born to mothers with any form of diabetes in pregnancy had a 50% increased risk of CAKUT compared with offspring of mothers without diabetes (relative risk [RR], 1.51; 95% confidence interval [CI], 1.36–1.67). Compared with offspring with nondiabetic mothers, offspring of mothers with pre-existing diabetes had an almost 2-fold rate of CAKUT (RR, 1.97; 95% CI, 1.52–2.54). Offspring of mothers with gestational diabetes had a 39% increased risk of CAKUT (RR, 1.39; 95% CI, 1.26–1.55) compared with offspring of mothers with no diabetes. The subset of studies that adjusted for body mass index (BMI) before pregnancy showed similar associations. Population attributable risks for gestational diabetes were estimated to be 3.7% of cases of CAKUT in the United States, 4% of CAKUT cases in the United Kingdom, with up to 14.4% CAKUT cases in the South Asian population in the United Kingdom. CONCLUSION: This study suggests that 2.0% to 3.7% of cases of CAKUT in the United States, and up to 14% of CAKUT in some populations could be eliminated if gestational diabetes was prevented or eliminated.