Sexual pain and IC/BPS in women

Dyspareunia is rarely assessed in rodent models of endometriosis and interstitial cystitis/bladder pain syndrome

Abstract

Dyspareunia, or pain during sex, is a common and often debilitating symptom in individuals with endometriosis and/or interstitial cystitis/bladder pain syndrome (IC/BPS). Despite its significant impact on quality of life, it is frequently overlooked in research. This review evaluates how dyspareunia has been addressed in preclinical investigations of these conditions. A systematic search was conducted using Embase from 1998 to 2021, identifying original in vivo preclinical studies using female rodents to model (i) endometriosis and (ii) IC/BPS. The search aimed to identify studies that assessed dyspareunia. Study quality and risk of bias were evaluated using a modified CAMARADES checklist. Our analysis found 1,286 studies modelling endometriosis and 674 modelling IC/BPS, but only 18 and 1, respectively, measured dyspareunia. The most common method involved vaginal distention in rats, assessed by either behavioural escape responses or visceromotor reflexes of abdominal muscles. Despite the high prevalence of dyspareunia in these conditions, it is rarely measured in preclinical studies. We identify a significant gap in the literature and offer succinct recommendations for future translational research to address this important symptom.

Lay summary

Dyspareunia describes pain occurring before, during or after sexual intercourse. This poorly understood symptom is particularly common in people suffering from two chronic pain-related conditions: endometriosis and IC/BPS, severely impacting their quality of life. Therefore, effective treatments addressing painful sex in people with these conditions are needed. To see the benefits of medical research at the patient's bedside, it is important to build from basic science research to preclinical animal studies then to human studies. Our study aims to assess the work that has been done so far at the 'preclinical' stage. Developments have been made in the methodology used to investigate this symptom in animals, and a summary of all the key findings may help build a platform to design future studies. Given the urgent need to develop new therapeutic strategies, attention given to painful sex by scientific medical researchers and physicians needs to improve.

Genital Pain and the Spectrum of Bladder-Related Symptoms: Findings from the Prevention of Lower Urinary Tract Symptoms Research Consortium RISE FOR HEALTH Study, USA

INTRODUCTION AND HYPOTHESIS

Women with vulvovaginal or genital pain more commonly experience interstitial cystitis/bladder pain syndrome (IC/BPS) and urinary tract infections. However, the relationship between genital pain and bladder health is lacking.

METHODS

Women in the Prevention of Lower Urinary Tract Symptoms Consortium's RISE FOR HEALTH population-based study answered questions about bladder health globally, and across nine bladder health domains of holding, efficacy, social-occupation, physical activity, intimacy, travel, emotion, perception, and freedom. Bladder function was assessed across six indices including urinary frequency, sensation, continence, comfort, emptying, and dysbiosis (e.g., urinary tract infections). Participants were grouped by no pain beyond transitory events (i.e., minor headaches, toothaches, or sprains), nongenital-related pain only, and any genital pain using a validated pain diagram. Mean adjusted scores and indices were compared using general linear modelling.

RESULTS

Of 1,973 eligible women, 250 (12.7%) reported genital pain, 609 (30.9%) reported nongenital pain only, and 1,114 (56.5%) reported no pain. Women with any genital pain had lower (worse) adjusted mean scores across all bladder health scales (BHS; BHS global adjusted mean 47.5; 95% CI 40.8-54.1), compared with those with nongenital pain only (53.7; 95% CI 47.6-59.8), and no pain (59.3; 95% CI 53.3-65.4). Similarly, adjusted mean total Bladder Functional Index scores were lower for those with genital pain (63.1; 95% CI 58.4-67.9) compared with nongenital pain (72.1; 95% CI 67.7-76.5) and no pain (77.4; 95% CI 73.0-81.8).

CONCLUSIONS

Heightened awareness of the relationship between genital pain and bladder health should prompt clinicians caring for women with genital pain to assess bladder health and function.

Examining vaginal and vulvar health and sexual dysfunction in patients with interstitial cystitis (UNICORN-1 study)

INTRODUCTION AND HYPOTHESIS

The Vaginal Health Index Score (VHIS) and vulvodynia swab tests are used to assess vaginal health and vulvodynia. However, few studies have used these tests in patients with interstitial cystitis/bladder pain syndrome (IC/BPS). IC/BPS is a chronic, debilitating disorder, characterised by urinary frequency, urinary urgency and pelvic pain. It adversely affects organs adjacent to the urinary system, leading to complications of sexual dysfunction. This study was aimed at understanding sexual dysfunction in patients with IC/BPS, as well as deterioration of vaginal health and vulvodynia.

METHODS

This study compared the vaginal health of IC/BPS patients with that of asymptomatic control individuals. The Pain Urgency Frequency (PUF) score, Female Sexual Function Index (FSFI), VHIS, and vulvodynia swab tests, were used as tools. The PUF and FSFI are questionnaire-based surveys of bladder symptoms and sexual function respectively. VHIS evaluation and vulvodynia swab tests are performed by physicians. The PUF was used to assess baseline IC/BPS symptoms to validate the patient population, and FSFI, vulvodynia swab tests and VHIS were used to determine between-group differences.

RESULTS

Thirty-seven patients were recruited in each group. The IC/BPS group had a higher PUF score (18.19±3.51 vs 3.56±2.35; p<0.05), worse total FSFI (15.72±4.46 vs 26.3±4.93; p<0.05), and worse vulvodynia swab test and total VHIS (11.59±2.87 vs 22.05±3.05; p<0.05) scores than those of the control group.

CONCLUSIONS

Asian women with IC/BPS experienced greater sexual dysfunction, worsened vaginal health and increased vulvodynia compared with control individuals. Information on vaginal and vulva health is very useful in evaluating IC/BPS patients.