Letrozole for ovulation induction and fertility preservation by embryo cryopreservation in young women with endometrial carcinoma

Objective: To reduce estrogen exposure in women with endometrial cancer undergoing in vitro fertilization using an aromatase inhibitor. Design: Prospective case series. Setting: Academic center for reproductive medicine. Patient(s): Endometrial carcinoma patients presenting for fertility preservation or fresh embryo transfer to gestational carrier. Intervention(S): Four patients with endometroid carcinoma underwent five IVF cycles for immediate or delayed embryo transfer to gestational carriers before or after staging and definitive surgery. To prevent surge in E-2 levels, letrozole was started 2 days before gonadotropin administration and then given concomitantly. Embryos were either cryopreserved for fertility preservation or transfered freshly to a surrogate. Main Outcome Measure(s): Peak E-2 level during stimulation, pregnancy in a gestational carrier. Result(s): Peak E2 level during stimulation was 386.67 +/- 102.93 pg/mL. A mean of 7 +/- 2.85 oocytes were retrieved, resulting in 4.8 +/- 1.76 embryos per cycle. In one patient, two embryos were transfered to a surrogate, resulting in a triplet pregnancy. The delivery occurred at 31 weeks and the infants did not show any congenital or developmental abnormalities. Three patients had their embryos cryopreserved for future use. Conclusion(s): The use of letrozole and gonadotropins is associated with lower E-2 levels compared with standard stimulation cycles in endometrial carcinoma patients. Combination of this approach with surrogacy may enable these young women to preserve their fertility.