Objective: To elucidate the prognostic factor for IVF&ICSI cycle cancellation in patients with endometriosis related infertility Design & Setting The study was a retrospective cohort study and conducted at Uludag University School of Medicine, ART center, between the years 2011-2017. Population Electronic database were screened and infertile patients with endometriosis, patients without male factor, systemic disease, undefined adnexal mass and aged <40 yrs were selected. Cycles were divided in two groups. (Cancelled vs. Embryo transferred) Results 44 cycles were cancelled and in 178 cycles embryo was able to transferred. When the groups were compared Age, day3 FSH were statically higher and AMH, AFC were statically lower in cycle cancelled (CC) group. Presence of adenomyosis was higher in CC group. (64% vs. 40% p<0.01) Surgery rate with laparotomy was higher in CC group. (54.5% vs. 13.5% p<0.01) AFC (OR:0.81, CI:0.70:0.93) remained as only independent factor associated with prognoses of IVF cycle with binary logistic regression analysis. Cancellation rates were similar between the phenotypes of endometriosis. Conclusions: Poor ovarian reserve, advanced age, presence of adenomyosis and the history of laparotomy are negative prognostic factors associated with IVF&ICSI cycle cancellation in endometriosis related infertility. AFC is the only independent factor to predict cycle cancellation. Phenotype of endometriosis does not affect the results. There is no funding in this study. Key Words: Endometriosis, Infertility, Adenomyosis, Intracytoplasmic Sperm Injections,