Objective To investigate the relationship between the five-circuit and six-qi characteristics of birth dates and the prevalence of endometriosis(EMs).Methods Clinical data from 333 EMs patients treated at the Department of Reproductive Medicine,The First Affiliated Hospital of Henan University of Chinese Medicine between March 2022 and March 2025 were collected.Statistical analysis was performed on parameters of the five circuits and six qi of patients' birth dates.Results No statistically significant differences were found in the distribution of heavenly stems,dominant circuits,guest circuits,dominant qi,guest qi,joining of guest qi with dominant qi,or Sitian-Zaiquan among the 333 EMs patients(all P＞0.05).However,significant differences were observed in the distribution of earthly branches,yearly circuits,and circuit-qi combinations(P＜0.05 or P＜0.01).Specifically:(1)The most frequent earthly branch was the"Wei"year(12.3％,41/333);(2)The most common annual circuit was"deficient water circuit"(14.7％,49/333);(3)The predominant circuit-qi combination was"Tong Sui Hui"(23.1％,77/333).Conclusion The development of EMs is associated with specific five circuits and six qi characteristics at birth:(1)Earthly branch of"Wei"year;(2)Annual circuit of"deficient water circuit";(3)Circuit-qi combination of"Tong Sui Hui".These patterns suggest that congenital endowmentl deficiencies in the spleen and kidney systems may predispose individuals to EMs.