Risk factors for urinary tract infection in the postpartum period.

OBJECTIVE: We sought to examine risk factors for urinary tract infection in postpartum women.

STUDY DESIGN: Subjects (n = 931) with maternal urinary tract infections and control subjects (n = 1862) were identified by using a linked Washington State birth certificate and Birth Events Records Database for the years 1987-1993; stratified analysis was performed by using Mantel-Haenszel procedures.

RESULTS: Increased risk for postpartum urinary tract infection was associated with black, Native American, or Hispanic race-ethnicity (odds ratio, 1.30; 95% confidence interval, 1.03-1.64) and unmarried status (odds ratio, 1.33; 95% confidence interval, 1.11-1.58). Cesarean delivery (odds ratio, 2.70; 95% confidence interval, 2.27-3.20) and tocolysis (odds ratio, 3.30; 95% confidence interval, 2.15-5.06) also contributed to maternal risk of acquiring a urinary tract infection. Maternal risk factors included renal disease (adjusted odds ratio, 3.89; 95% confidence interval, 1.80-8.41) and preeclampsia-eclampsia (adjusted odds ratio, 3.21; 95% confidence interval, 2.36-4.38). Among women undergoing vaginal delivery, renal disease (odds ratio, 5.47; 95% confidence interval, 2.04-14.64) and abruptio placentae (odds ratio, 5.02; 95% confidence interval, 1.84-13.64) were risk factors. Length of hospital stay was significantly associated with urinary tract infection.

CONCLUSION: Maternal medical conditions and procedures that predispose to urinary tract infections are those that also are associated with urethral catheterization. In addition, maternal urinary tract infections may contribute significantly to duration of postpartum hospital stay.