A single institution study evaluating the fertility of young adults with malignancy treated with immunotherapy and early referral to oncofertility providers.

e23254 Background: Immune checkpoint inhibitors (ICIs) are used among multiple types of cancers. However, there are limited studies on the long-term effects of ICIs on fertility. Our study seeks to examine factors influencing conception after treatment with ICIs and referral rates to our oncofertility program. Methods: 184 female patients between the ages of 18-45 with malignancies were treated with ICIs from January 2012 to December 2023 at a single tertiary medical center. 2 patients were excluded due to limited reproductive data. Demographics, oncologic, fertility, and reproductive data were collected. Results: Of 184 patients, 68 (37.0%) had documented fertility discussions prior to initiation of ICIs and 36 (19.6%) patients were referred to reproductive medicine. Of the referred patients, the median age at time of ICI initiation was 32 years and 27 (75%) were Caucasian. The most common cancers were breast adenocarcinoma (52.8%), hematologic malignancies (25%), and melanoma (13.9%). 21 (58.3%) underwent a fertility preservation cycle (oocyte or embryo cryopreservation). One patient received ovarian stimulation but oocyte retrieval was not performed due to poor response. There were 3 individuals with successful pregnancies; 3 were previously treated with nivolumab and 2 with chemotherapy. Of the 3 individuals, one individual used in vitro fertilization (IVF) using frozen embryo transfer to conceive, resulting in 2 full-term live births. The other two conceived via natural conception, resulting in one full-term live birth each. Time to conception ranged from 12-27 months following ICI completion. Conclusions: Early referral to oncofertility providers in young adults with cancer can increase rates of successful conception and increase utilization of fertility preservation methods. Larger multi-institutional studies are needed to further delineate the long-term effect of ICIs on fertility. Reproductive data for individuals with successful conception following ICI treatment. Patient 1 2 3 Age at time of ICI 24 22 21 Diagnosis Hodgkin Lymphoma Melanoma Hodgkin Lymphoma Stage IV IIIA IIA ICI received Nivolumab Nivolumab Nivolumab Number of Pregnancies Prior to ICI 0 0 1 Number of Successful Pregnancies Following ICI 2 1 1 Fertility Preservation Method Embryo cryopreservation Declined Oocyte cryopreservation Mode of Pregnancy IVF Natural Natural Duration After Treatment Until Pregnancy (mo) 12 15 27