Maternal Kidney Disease Linked to Higher Congenital Malformation Risk

A LARGE nationwide cohort study suggests that babies born to mothers with kidney disease face a modestly increased risk of congenital malformations, highlighting the need for careful monitoring and counselling during pregnancy.Researchers analysed data from more than 2.6 million women who gave birth between 2008 and 2017 using the Korean National Health Insurance Service database. The investigators aimed to clarify whether maternal kidney disease, including chronic kidney disease (CKD) and end-stage kidney disease (ESKD), is associated with a higher likelihood of major congenital anomalies in offspring, an area where previous evidence has been limited.

Risk Higher in CKD and More Pronounced in End-Stage Kidney DiseaseMajor congenital malformations were identified using ICD-10 diagnostic codes recorded within the first year of life. The prevalence of major anomalies was 4.79% among infants born to healthy mothers, rising slightly to 5.29% in those born to mothers with CKD and more markedly to 9.65% in those whose mothers had ESKD. Congenital heart defects were the most frequently reported anomalies across all groups.After adjusting for potential confounding factors, maternal kidney disease remained associated with an increased risk of congenital malformations. Compared with healthy controls, mothers with CKD had a small but statistically significant increase in risk (adjusted odds ratio aOR] 1.07; 95% CI 1.03–1.11). The risk was higher among mothers with ESKD (aOR 1.71; 95% CI 1.16–2.52). Within the ESKD subgroup, women who had received a kidney transplant also showed an elevated risk (aOR 1.65; 95% CI 1.06–2.59), whereas the association did not reach statistical significance among those undergoing dialysis.

The authors note that although the absolute risk increase in CKD was relatively modest, the findings are clinically relevant given the growing number of pregnancies in women with chronic medical conditions. Potential explanations may include disease severity, comorbidities, medication exposure, or altered maternal physiology, though causality cannot be established from this observational design.