Objective: Previous research has indicated a link between coeliac disease (CD) and urinary tract infection (UTI). The objective of this study was to assess the risk of UTI and repeated episodes of UTI before the current pregnancy in women with diagnosed or undiagnosed CD.
Material and methods: A national registry-based cohort study restricted to pregnant women was used in this investigation, with linkage between the Swedish National Medical Birth Registry and the National Inpatient Registry. We analysed the risk of UTI during pregnancy from 1973 to 1989 in 212 pregnancies to women who had received a diagnosis of CD prior to giving birth and in 786 pregnancies to women diagnosed after giving birth. We also assessed the risk of repeated episodes of UTI before the current pregnancy according to data in the national birth records of 1990-2001 in 617 women with CD diagnosed prior to giving birth and 109 women diagnosed after giving birth.
Results: UTI during pregnancy: UTI occurred during 19,139/1,678,304 pregnancies to women who had never had a diagnosis of CD, compared with in 12/786 pregnancies to women with undiagnosed CD (adjusted odds ratio (AOR)=1.37; 95% CI=0.78-2.43; p=0.276) and in 0/212 pregnancies to women with diagnosed CD (AOR=0.06; 95% CI=0.00-8.94; p=0.277) (ORs adjusted for maternal age, parity, nationality and calendar period). Repeated episodes of UTI before the current pregnancy: among 692,991 women who had never had a diagnosis of CD, 74,776 reported repeated episodes of UTI, compared with 14/101 women with undiagnosed CD (AOR=1.39; 95% CI=0.79-2.45; p=0.255) and 69/566 women with diagnosed CD (AOR=1.02; 95% CI=0.79-1.32; p=0.864) (ORs adjusted for maternal age, parity, nationality, calendar period and civil status). Adjustment for smoking in a subset of patients with available data did not change the risk estimates.
Conclusions: It cannot be ruled out that undiagnosed CD in pregnant women is associated with a small, increased risk of UTI. In pregnant women with diagnosed CD, there seems to be no increased risk of UTI.