Clinical presentation and management of urolithiasis in the obstetric patient: a matched cohort study.

Purpose: To evaluate the effect of pregnancy on the clinical presentation, inpatient procedure rates, and length of hospital stay, on women with urolithiasis.

Materials and methods: We carried out a matched cohort study using the United States' Healthcare Cost and Utilization Project-Nationwide Inpatient Sample database from 1999 to 2015. Pregnant women with urolithiasis were compared to age-matched non-pregnant women (1:1) with urolithiasis. Baseline clinical characteristics were compared between the two cohorts and the effect of pregnancy on select inpatient procedural and clinical outcomes was evaluated using conditional logistic regression models.

Results: There were 42,113 pregnant patients diagnosed with urolithiasis during the study period. It was observed that pregnant patients were less likely to present with classic clinical symptoms of urinary tract stones, such as flank pain, OR 0.63, 95% CI 0.56-0.70, and fever, 0.22 (0.16-0.30), but tended to have longer hospital stays. The pregnant patients were less commonly affected by infectious conditions, namely urinary tract infections, 0.56 (0.53-0.59), sepsis, 0.17 (0.14-0.20), and pyelonephritis, 0.34 (0.36-0.44). Invasive and surgical procedures were less commonly performed in pregnant women.

Conclusions: Pregnant women admitted with urolithiasis appear to be less symptomatic with fewer interventions and complications than non-pregnant women with urolithiasis.