Scientists hope to make a baby from a frozen testicle

Doctors stunned the world last week when they revealed that they had helped a 27-year-old woman give birth—using ovarian tissue cryopreserved a decade earlier.

The mother battled sickle cell anemia as a child and froze the tissue when she was 13 years old, before undergoing chemotherapy, which can imperil fertility. What’s especially remarkable is that the patient hadn’t started menstruating at the time of the procedure—she didn’t get her first period until doctors grafted the tissue onto her remaining ovary in her twenties. She became pregnant just a few years later.

Related: How do you make a baby from a frozen ovary? Like this.

The birth marks a medical milestone for girls facing chemo and other harsh radiation therapies. But the breakthrough made us wonder: What options exist for boys in similar situations? Are scientists trying to help men have children through frozen testicle tissue?

We posed these questions to two experts: Paul Turek, founder of The Turek Clinic, a bicoastal medical group dedicated to men’s sexual health and fertility, and Kyle Orwig, a leader of the Fertility Preservation Program at the University of Pittsburgh Medical Center.

How can males preserve future fertility?

If a male has gone through puberty, doctors will recommend that he freeze his sperm before chemo or any harsh radiation treatment. “It’s the lowest hanging fruit in the world of fertility preservation,” said Turek.

Down the road, when the patient is ready to have a child, his sperm can be thawed and used for artificial insemination or in vitro fertilization. (Similarly, a woman who has gotten her period will often opt to freeze her eggs before undergoing chemo or radiation therapy.)

For males who haven’t gone through puberty, however—and thus aren’t producing sperm—there are no proven ways to preserve fertility. And this a problem, said Orwig, given that thousands of boys and early teens develop cancer or other conditions that require radiation treatment or chemo in this country every year, and many survivors will struggle to have children. But, we learned, scientists are working on innovative solutions.

How will males preserve fertility in the future?

While these proposed solutions are still many years from becoming a reality, the science behind them is fascinating—and the promise immense. Like many of the medial innovations in the works today, they’re all grounded in stem cell technology.

Here’s the premise: Males are born with stem cells in their testes that eventually give rise to cells that produce sperm at puberty—so the key to helping boys who haven’t gone through puberty preserve fertility may be to isolate and freeze those stem cells prior to treatment.

Today, multiple research teams are working on technology to make a stem cell option possible. Most likely, the procedure would involve removing tissue from a young patient’s testicle prior to radiation or chemotherapy, freezing the tissue, then thawing it down the road—with the hope that stem cells from the sample could be used to produce sperm.

Orwig told Fusion that this process has been successfully tested in monkeys, and is now ready for human study.

Sperm without testicles

Turek is also attempting to tackle male infertility himself—in a way that could bypass the testicle altogether. A group of scientists in his Beverly Hills office are working on creating a device that mimics the testicle to produce sperm from stem cells extracted from a variety of organs.

“We are trying to recreate the entire environment of the testicle,” Turek told Fusion. “Including the major cell types and their architectural arrangement in tubes, to show the stem cells that ‘this is the way to go forward’ and become sperm. Thereby growing sperm outside of the body.”

Turek hopes that, someday, doctors will be able to use the machine to help young cancer survivors have children. The process would involve removing stem cells from the patient (say, from the skin), then harvesting them in the device to eventually produce sperm.

The treatment could also be used to help adult men suffering from permanent injuries to their testicles or men facing genetic infertility.

Potential clinical use is still many years away—but it’s safe to say that if Turek figures out how to create one of the building blocks of human life inside a fake testicle machine, the breakthrough will make headlines.

Cleo Stiller is a digital producer covering the intersections of sex, tech and culture. Words to live by: get your money’s worth.