For years, doctors have sought ways to restore lost bodily functions. The earliest prosthetic limbs date back to ancient Egypt, but today’s modern upgrades involve high-tech actuators and even AI. Scientists have even made artificial organs that can replace a patient’s kidneys or heart. Now, they’ve taken things a step further: the first penis prosthetic.

In trials with rabbits and pigs that had damaged penis tissue, the 3D printed penis was able to restore sexual function. It points to a future where customized, bioengineered penile prosthetics could offer a solution for erectile dysfunction, penis injuries, and other conditions affecting the male reproductive system.

From the Lab to the Barnyard

Locker room jokes aside, the penis is actually an intricate organ. It’s designed to function through a precise interplay of blood vessels, spongy tissue, and nerve signals. But the more moving parts, the higher the risk of malfunction.

For years, scientists have have struggled to recreate its structure in the lab. The biggest challenge is replicating the corpus cavernosum — the vascular tissue responsible for erections — and ensuring that an implant interacts seamlessly with the body, including arousal stimuli and sperm-producing gonads.

The research team approached this challenge by designing a 3D-printed model that included the corpus spongiosum (which surrounds the urethra), the glans (the tip of the penis), and a biomimetic corpus cavernosum (BCC). They used a hydrogel material that mimics soft tissue while allowing blood to flow and expand as it would in a natural erection. They then seeded the implants with endothelial cells — the lining of blood vessels — to promote integration with existing tissues.

Once the implants were developed, the researchers tested them in animal models. Rabbits and pigs with partial penile injuries underwent surgery to receive the bioengineered implants. Within weeks, these animals regained erectile function. When introduced to mates, they were able to copulate and reproduce with a 100% success rate.

“The fertility of the [endothelial cell] groups demonstrates the recovery of erectile function and the ability to ejaculate, suggesting the restoration of the cavernous tissue in the treated males,” the researchers wrote in their study published in Nature Biomedical Engineering.

Complex Challenges Remain

By enabling natural erections and successful reproduction, the study suggests that similar implants could one day help humans with conditions like erectile dysfunction, penile trauma, or deformities such as Peyronie’s disease. The latter causes painful curvature of the penis, and can also lead to dysfunction. Erectile dysfunction affects over 40% of men over 40, and its causes range from nerve damage to hormonal imbalances.

However, this technology is still in its early stages and it’s definitely not ready for humans. The implants were only tested in cases of partial tissue damage, and the researchers acknowledge that repairing more severe injuries is a different ball game.

If you’re suffering from ED, you don’t to get an impact to potentially see dividends from these findings. Beyond its potential as a treatment, the 3D-printed model offers a new way to study erectile dysfunction. By simulating the flow of blood and the interaction of tissues during an erection, scientists can better understand what goes wrong in cases of dysfunction. The lessons they learn may translate into new treatments — ones that don’t require you sporting a cyborg penis.

Meanwhile, the team hopes to refine their model to include nerves, blood vessels, and urethral structures. Human sex is not just about reproduction but also very important for intimacy, so an implant would have to cover a lot of features to be truly appealing. “Future research could explore design strategies aimed at inducing nerve regeneration and embedding artificial blood vessels and urethral structures within the implants,” the researchers wrote.