Correlation Between the Age at Menarche, Time to Diagnosis, and Disease Severity Assessed Using the rASRM and #ENZIAN Classifications in Patients Diagnosed with Advanced Endometriosis

Background/Objectives: Endometriosis is a chronic inflammatory gynecological condition characterized by a highly variable clinical picture, with pain at multiple sites being among its most disabling features. Women are mostly diagnosed between 20 and 45 years of age, but the time from symptom onset to diagnosis varies across countries, from a few months to more than a decade. Symptoms unequivocally linked to disease onset are difficult to identify, since hormonal activity during puberty varies between individuals. This study assessed the relationship between the age at menarche and the duration, regularity, heaviness, and painfulness of the first menstrual bleedings and the occurrence and severity of endometriosis. Methods: This retrospective study included 188 patients with advanced endometriosis qualified for surgical excision of endometriotic lesions between 1 May 2024 and 31 May 2026. Data were obtained through a detailed history taken as part of a preoperative questionnaire. The severity of endometriosis was assessed intraoperatively according to rASRM and #ENZIAN systems. Validated statistical tests were applied, with p-value < 0.05 considered significant. Results: No significant correlation was found between the age at menarche and the duration, regularity, or heaviness of the first menstrual bleeding and rASRM-assessed severity. A positive correlation was observed between symptom duration, in years, and first-menstruation pain intensity, and between later menarche and #ENZIAN P and T localization. Conclusions: The age at menarche, disease duration, and diagnostic delay do not consistently correlate with rASRM-assessed severity. These findings should be interpreted with caution given the selected cohort and may not generalize to patients with milder disease or those managed non-surgically.