Endometriosis symptoms often first appear during adolescence, yet delays in seeking gynecologic consultation remain a persistent challenge worldwide. Despite growing international evidence, the specific patterns of symptom recognition and consultation delay among Japanese women — particularly in relation to self-monitoring behaviors and cultural barriers — remain poorly understood. This study aimed to provide foundational data to guide menstrual education and preconception care strategies by conducting a cross-sectional online survey with retrospective recall among women with endometriosis to assess menstrual characteristics and symptom patterns from adolescence to initial care seeking. The survey was conducted in Japan in January 2024 and enrolled 166 women with endometriosis and 200 controls. Participants reported current and adolescent menstrual characteristics, symptom recognition, analgesic and low-dose estrogen–progestin use, school/work impact, and age at first gynecologic consultation for menstrual problems. Women with endometriosis reported heavier bleeding, stronger pain, and greater school/work absence than controls, both currently and retrospectively. The median age at first recognition of heavy bleeding or school/work absence was 16 years, whereas consultation occurred at approximately 21-23 years, indicating a consultation delay of 5-6 years. Notably, while self-monitoring of symptoms was more frequent among women with endometriosis, it only modestly shortened consultation delays. This study provides evidence from Japan that consultation delay persists despite active self-monitoring of symptoms, highlighting the influence of educational and cultural barriers on health-seeking behavior. These findings underscore the importance of integrating menstrual education with clinical guidance to promote timely gynecologic consultation.