The association between cervical conization and subsequent development of endometriosis is uncertain. The objective of this study was to estimate the incidence rate of ovarian endometrioma after cervical conization and to determine factors associated with the development of endometrioma. One hundred forty-two patients who underwent cervical conization at the University of Tokyo Hospital between January 2006 and December 2013 were included in the study. Their medical records were retrospectively studied until April 2015. The incidence rate of postconization endometrioma was calculated. Patients' characteristics (age, parity, preoperative and postoperative diagnosis and observation period) were analyzed. Six patients developed endometrioma after the cervical conization, and the incidence rate of endometrioma among patients who underwent cervical conization was 10.8 per 1000 person-year (95%CI 3.6-20.5). Patients' age, percent of nulliparous, postoperative diagnosis and observation period were not associated with the development of postconization endometrioma. A preoperative diagnosis with invasive cancer (p < 0.05) was significantly associated with the development of postconization endometrioma. The incidence rate of endometrioma among patients who underwent cervical conization in the current study was higher than that reported population.
Keywords: Cervical intraepithelial neoplasia; cervical cancer; cervical conization; endometrioma; endometriosis.