Fertility treatment using assisted reproductive technology during immune checkpoint inhibition: report of two cases.

There are limited data to guide fertility counseling for patients on prolonged immune checkpoint inhibition. Concerns include potential teratogenicity, decline in ovarian reserve and spermatogenesis, and endocrine immune-related adverse events such as hypophysitis. As indications for checkpoint inhibition expand, an increasing number of reproductive-aged patients face fertility-related decisions around active therapy. We present two patient cases, one male and one female, who used assisted reproductive technology to support family building during maintenance immune checkpoint inhibitor therapy. A female lung cancer survivor underwent in vitro fertilization and froze six euploid blastocyst embryos for gestational surrogacy. A male gastroesophageal junction cancer survivor and his female partner underwent in vitro fertilization followed by a medicated intrauterine insemination cycle to conceive healthy fraternal twins. While prospective data are needed, this case series supports the feasibility of fertility treatment during checkpoint inhibitor therapy and highlights remaining clinical questions regarding this important aspect of cancer survivorship.