Abstract
To avoid complications related to mid-urethral slings (MUS), alternative procedures to treat stress urinary incontinence (SUI), such as urethral bulking agents (UBAs) have been adopted. The aim of this review is to narratively report the efficacy and safety of UBAs for SUI treatment. For this review, research from PubMed and EMBASE was performed to evaluate relevant studies that were undertaken from January 2012 to January 2022. Nineteen prospective studies were included. Several definitions of subjective and objective success were adopted. At a follow-up of <24 months, significant improvement was widely observed, even if with a heterogeneous rate of success between 32.7−90%, and a reinjection rate of 8.3−77.3%. Compared with other procedures, MUS resulted as significantly superior to UBAs but was balanced by a higher complication rate. Acute urinary retention, urinary tract infection and de novo urgency, and other complications, such as injection site rupture, urethral erosion and particle migration have been described after UBAs. SUI after UBAs treatment resulted in improvements in all studies and can be considered a safe and effective option to treat SUI. However, homogenous and longer-term data lack, limiting general recommendations. Thus, larger RCTs evaluating long-term effects are required.