Early-Stage Pelvic Organ Prolapse and Associated Pelvic Floor Symptoms in Japanese Women Attending Routine Gynecological Screening.

Background Pelvic organ prolapse (POP) is a common but often underrecognized condition affecting women's quality of life worldwide. While severe or symptomatic prolapse has been the primary focus of most prior studies, there is limited information on the prevalence and symptom burden of early-stage POP in Asian populations, particularly among women who may not actively seek medical care. Establishing the presence and clinical significance of mild prolapse is essential to inform prevention, early detection, and patient education strategies. Objective The aim of this study was to evaluate pelvic organ support and associated pelvic floor symptoms in a large cohort of Japanese women, with particular emphasis on early-stage prolapse. We sought to clarify whether mild prolapse, often considered clinically insignificant, is in fact associated with specific and bothersome symptoms. Methods This single-center, cross-sectional study recruited Japanese women seeking a routine Pap smear, representing an asymptomatic or unselected general population, from July 2018 through May 2019. Women who were pregnant or had given birth in the previous six months, were using a pessary for POP, or had a history of surgery for POP or incontinence were not included. Participants completed a questionnaire covering nine symptoms based on the Japanese Pelvic Floor Distress Inventory, i.e., frequent urination, urge urinary incontinence, stress urinary incontinence (SUI), urine leakage, difficulty emptying, pain or discomfort, pelvic heaviness or dullness, vaginal bulge, and anal incontinence. Pelvic organ support was assessed by a single examiner using the Pelvic Organ Prolapse Quantification (POP-Q) system, and participants were subsequently grouped by POP-Q stage. Each vaginal compartment (anterior, posterior, apical) was assigned a stage (0-IV), with an overall stage determined on the basis of the maximum point of descensus in each participant. Relationships between compartment-specific POP stages and symptom scores were analyzed using multiple regression, with a 5% significance level. Results A total of 1,023 women with a mean age of 52.1 (range: 21-84) years participated in the study. The overall distribution of POP-Q stages was as follows: stage 0, 390 (38.1%); stage I, 463 (45.3%); stage II, 165 (16.1%); and stage III, 5 (0.5%). No participants had stage IV POP. Nearly half of the women (493, 48.2%) experienced symptoms of SUI, and 78 (7.6%) reported a vaginal bulge, with significant differences in symptom prevalence (chi-square test, all p < 0.05). The most common prolapse combination involved both the anterior and posterior vaginal walls, with anterior descent occurring more frequently than posterior descent. Anterior prolapse was also associated with increased SUI at ≥ stage I (p < 0.05). Vaginal bulge sensation was significantly associated with ≥ stage II prolapse in all compartments (p < 0.01). There was no association between anal incontinence and any prolapsed compartment. Conclusion This study represents the first large-scale evaluation in Japan to examine both POP-Q-based pelvic support and its association with pelvic floor symptoms in a screening population. Our findings provide foundational epidemiological data that bridge the gap between clinical studies of severe POP and general population surveys, offering new insight into the natural history and symptom burden of early pelvic organ prolapse.