Frozen Embryo Transfer Linked to Small Increase in Cancer Risk in Offspring

By Amy Orciari Herman

Edited by David G. Fairchild, MD, MPH, and Lorenzo Di Francesco, MD, FACP, FHM

Frozen embryo transfer — but no other fertility treatments — may be associated with increased risk for childhood cancer in offspring, suggests a retrospective study in JAMA.

Using Danish birth and health registries, researchers studied over 1 million children born between 1996 and 2012. Some 84% were born to fertile women, while the remainder were born to women who required fertility treatment.

During an average follow-up of 11 years, the incidence rate of childhood cancer was higher among children born after frozen embryo transfer than among those born to fertile women (44 vs. 18 per 100,000 person-years). Leukemia accounted for most of the elevated risk, with five cases occurring after frozen embryo transfer. Other fertility treatments (e.g., clomiphene, IVF) were not associated with cancer risk.

Dr. Robert Barbieri of NEJM Journal Watch Women's Health will weigh in on these findings in the coming days. Stay tuned.