Shorter Anogenital Distance in Women with Adenomyosis Diagnosed by MUSA 2022 Criteria: A Prospective Case-Control Study

Abstract

Objective: The objective was to investigate the association between anogenital distance (AGD) and adenomyosis in reproductive-age women and to evaluate the potential of AGD as a non-invasive biomarker reflecting prenatal hormonal environment. Methods: This prospective case-control study included 40 women with adenomyosis diagnosed according to the Morphological Uterus Sonographic Assessment (MUSA) 2022 criteria and 40 age-matched healthy controls. Two AGD measurements were obtained: AGD-af (anus to posterior fourchette) and AGD-act (anus to clitoral tip). Measurements were performed by two independent observers using vernier calipers. Hormonal parameters, reliability analyses, receiver operating characteristic (ROC) curve analysis, and logistic regression were conducted. Results: Women with adenomyosis had significantly shorter AGD-af compared to controls (23.78 +/- 7.20 vs. 27.88 +/- 7.50 mm, p = 0.015), whereas AGD-act did not differ significantly (p = 0.574). Inter- and intra-observer reliability was excellent (intraclass correlation coefficient [ICC] = 0.87-0.93). ROC analysis revealed an area under the curve (AUC) of 0.658 (95% confidence interval [CI]: 0.55-0.76) for AGD-af (optimal cut-off = 24 mm; sensitivity: 57.5%, specificity: 67.5%). In multivariate logistic regression, AGD-af remained independently associated with adenomyosis after adjusting for age and body mass index (BMI) (adjusted odds ratio [OR] = 0.925, 95% CI = 0.866-0.989, p = 0.022). No significant difference was observed in hormonal parameters between groups. Conclusions: Women with adenomyosis exhibit a modest but significant reduction in AGD-af, suggesting a possible influence of prenatal hormonal environment in disease pathogenesis. Although its diagnostic accuracy is fair, AGD-af may serve as a complementary, non-invasive biomarker in clinical assessment of adenomyosis.