Pelvic anatomy and recurrent UTI in young women

Recurrent UTI (RUTI), a common problem in young women, has been associated with sexual intercourse, use of spermicides, blood group antigen nonsecretor status, and colonization with uropathogens having urovirulence determinants. Although the dramatic difference in risk of UTI between young men and women is assumed to be in large part due to the markedly greater length of the male urethra and its greater distance from the rectal microbial flora, corresponding anatomic measurements have not been compared in women with and without RUTI. We determined the following anatomic parameters in 95 young women with ≥3 UTIs in the past 12 months (cases) and 107 women with no UTI in the past year and no history of >1 UTI in any year (controls): urethral length (UL); distance from urethra to anus (UA); distance from posterior fourchette to anus (FA); and distance from urethra to hymen (UH). Postvoid residuals (PVR) were also determined with a catheter. Results are in Table. UL(cm) a UA(cm) a,b FA (cm) a,c UH(cm) a PVR(cc) a Cases 3.7+/- 0.4 4.8+/-0.6 2.6+/-0.5 0.9+/-0.2 43+/-41 Controls 3.6 +/- 0.4 5.0+/-0.7 2.8+/-0.5 0.9+/-0.2 49+/-48 a mean +/-SD; b p= 03; c p=.04 After controlling for sexual intercourse in non-spermicide users, cases were more likely to have UA <4.5 cm vs. controls (OR=5.7 [95% CI 2.0, 16.6]; p=.0013). This was not observed in spermicide users (OR=0.9 [95% CI 0.3, 2.6]; p=.90). We conclude that UL, UH, and PVR are not associated with RUTI in young sexually active women but that a shorter distance between the urethra and posterior fourchette or anus may have a role in predisposing some women to RUTI.