Random-start controlled ovarian hyperstimulation for emergency fertility preservation in letrozole cycles

Objective To report an emergency approach of random-start controlled ovarian hyperstimulation (COH) in the late follicular or luteal phase of the menstrual cycle for embryo cryopreservation in patients with cancer. Design Case series. Setting Academic tertiary referral centers. Patient(s) Three patients with a diagnosis of breast cancer requiring emergency fertility preservation in the late follicular or luteal phase of the menstrual cycle. Intervention(s) After baseline pelvic ultrasound and hormonal evaluation, random-start COH was commenced immediately on menstrual cycle days 11, 14, or 17 with use of letrozole 2.5 mg/d and recombinant FSH 150 to 300 IU/d. Gonadotropin-releasing hormone antagonist was administered to prevent ovulation in all cases. Ovulation was triggered with either 250 μg of recombinant hCG or 10,000 IU of urinary hCG. Main Outcome Measure(s) Number of oocytes harvested, maturity and fertilization rates, number of embryos frozen. Result(s) Nine to 17 oocytes were harvested, resulting in the freezing of seven to 10 embryos with the mean maturity and fertilization rates of 58.8% to 77.7% and 69.2% to 87.5%, respectively. Conclusion(s) In an emergent setting, ovarian stimulation can be started at a random cycle date for the purpose of fertility preservation without compromising fertilization rates in letrozole cycles.