Medications like chemotherapy and radiation are highly effective in treating cancer and benign tumors, but these therapies can also increase the risk of infertility. One in three childhood cancer survivors carry this risk, and for those undergoing treatment prior to puberty, common fertility preservation processes for adults—such as sperm or egg freezing—are not an option. 

But there may be newfound hope.

Recent research from the University of Pittsburgh School of Medicine, Magee-Women’s Research Institute and Oregon National Primate Research Center (ONPRC) at Oregon Health & Science University has found immature testicular tissue can be cryopreserved, or frozen, and later used to restore fertility.

Using a nonhuman primate model of cancer survivorship, the researchers removed one testis each from prepubertal rhesus macaques and cryopreserved the immature testicular tissue. Later, the researchers thawed and transplanted pieces of the tissue under the skin of the same animal.

Approximately one year later, the testicular skin grafts were removed and compared to samples of the immature tissues. Not only were the grafts able to produce enough testosterone for the animal to undergo puberty, but they were also found to contain an abundance of mature sperm.

Scientists at ONPRC then used the samples to generate viable embryos through intracytoplasmic sperm injection, or ICSI, where individual sperm were recovered from the graft tissues and injected directly into an egg. The embryos were successfully transferred to recipient females, and in April 2018, a healthy female baby named “Grady” was born.

“The ability and choice to have a family should not be determined by the risks of necessary medical treatment,” said Carrie Hanna, PhD, director of the Assisted Reproductive Technology Core at ONPRC. “Grady represents an important step toward ensuring that children maintain their opportunity to have a family later in life, should they choose to do so.”