Introduction and Hypothesis <p>Research on female patients with bladder pain syndrome/interstitial cystitis (BPS/IC) who have urethral, vaginal, perineal, or anal pain (pelvic-perineal pain, PPP) remains limited. This retrospective study characterized their clinical features and treatment outcomes.</p> Methods <p>From 2013 to 2023, a total of 130 female patients with BPS/IC were enrolled. Treatments included hydrodistension with Hunner lesion resection (when present), oral/intravesical medications, and pudendal nerve block for significant PPP. Recurrences were managed with repeat therapy or advanced options (platelet-rich plasma, botulinum toxin, sacral neuromodulation), with urinary diversion as the last resort.</p> Results <p>Among the cohort, 24 patients (18.46%) were identified as having PPP. These patients were significantly older and had higher symptom scores than those without PPP (all <i>p</i> &lt; 0.05). The PPP group exhibited a higher prevalence of cystoscopic grade 4 lesions and a smaller anesthetic bladder capacity. Furthermore, within the PPP cohort, the presence of grade 4 lesions and a bladder capacity ≤ 400&#xa0;ml were significant predictors of poor treatment outcome. Over a median follow-up of 74.8&#xa0;months, although overall improvement was not statistically different from a severity-matched control group, treatment failure necessitating urinary diversion occurred exclusively in the PPP group (12.5% vs 0%, <i>p</i> = 0.013). Furthermore, the PPP group required significantly more therapeutic interventions per patient (1.96 vs 1.17, <i>p</i> = 0.001).</p> Conclusions <p>A subset of female patients with BPS/IC presents who had concomitant PPP, which identifies a more severe disease phenotype characterized by objective markers of severity and a higher risk of treatment failure. The assessment of PPP serves as a straightforward and valuable prognostic marker in clinical practice.</p>