Immune checkpoint inhibitors and pregnancy: Considerations for treating medically complex patients with the best available therapy

In recent decades, the mean age of childbearing has increased in the United States and other developed countries, coinciding with a rise in cancer diagnoses during pregnancy. This trend is partly due to the increased use of assisted reproductive technologies and a decrease in the mean age of cancer onset for several malignancies. Concurrently, immune checkpoint inhibitors (ICIs) have become a standard treatment for various cancers, yet their safety during pregnancy remains under-researched. This article explores the complex intersection of cancer treatment and pregnancy, focusing on the use of ICIs. Despite societal concerns, data on the safety of ICIs during pregnancy are limited, primarily derived from preclinical animal studies and case reports. While most case reports suggest no significant adverse effects on live births, isolated incidents of severe neonatal complications have been documented. The potential for immune-related adverse events (irAEs) in neonates, such as thyroiditis or enterocolitis, underscores the need for caution. Given the lack of comprehensive data, clinicians face challenging decisions when treating pregnant cancer patients, particularly in metastatic settings where ICIs may be the only viable option. This article advocates for a careful risk-benefit analysis and informed patient discussions, emphasizing the need for further research to guide clinical decision-making in these complex scenarios.