%0 Journal Article %T A Retrospective Study on the Use of High-Dose Letrozole While Undergoing Ovarian Stimulation for Oocyte and Embryo Cryopreservation in Cancer Patients %A Rahana Harjee %A Jeffrey Roberts %J Advances in Reproductive Sciences %P 19-26 %@ 2330-0752 %D 2022 %I Scientific Research Publishing %R 10.4236/arsci.2022.101003 %X Objective: To determine the efficacy of letrozole in suppressing estradiol levels during ovarian stimulation in cancer patients. Methods: A retrospective chart review of cancer patients undergoing ovarian stimulation for fertility preservation between 2014-2019 at a private university-affiliated fertility clinic in Canada was conducted. Ovarian stimulation was completed with no letrozole (Group A, n = 10), and adjuvant daily letrozole use at 5.0 (Group B, n = 34) or 7.5 mg (Group C, n = 61). The primary outcomes were peak estradiol levels and oocyte yield. ANOVA with a post hoc two-tailed t-test assuming equal variance was utilized as a statistical method. Result(s): Patient age and AFC count were not different between groups. The yield of mature eggs was not different at each letrozole dose; 9.2 ¡À 6.0, 13.9 ¡À 6.5 and 12.7 ¡À 7.2 for Groups A to C respectively (p = 0.18). Mean estradiol levels(pmol/L) were reduced in a dose-dependent manner; 7432 ¡À 4553 for Group A, 2072 ¡À 1656 for Group B, and 1445 ¡À1238 for Group C (A vs. C,