Congenital anomalies of the kidney and urinary tract (CAKUT) are significant causes of pediatric morbidity and mortality.

The spectrum of CAKUT can be part of a syndrome, but most of these abnormalities occur as isolated and sporadic forms. The etiology of human CAKUT is unknown in the majority of cases.

This case–control study aimed to investigate the association between maternal characteristics and the occurrence of CAKUT and specific CAKUT phenotypes.

In this case–control study, 29,653 newborns were evaluated consecutively in a tertiary neonatal unit using the Latin American Collaborative Study of Congenital Malformations (ECLAMC) registry.

Newborns without congenital anomalies were matched to CAKUT cases by sex, date, and place of birth at a ratio of 3:1. For analysis purposes, the cases were stratified into four subgroups: upper tract abnormalities (UTA), including ureteropelvic junction obstruction, vesicoureteral reflux, primary megaureter and others (n = 239), lower urinary tract obstruction (LUTO) (n = 79), cystic diseases (n = 59) and agenesis/hypodysplasia (n = 28).

Multivariable logistic regression analyses were used to calculate crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) for associations between the maternal risk factors and the presence of CAKUT.