For couples who have been told there is no viable sperm to work with, that verdict has long meant the end of the road for biological parenthood. A new artificial intelligence method developed at Columbia University Fertility Center is starting to change that.
The system, called STAR, has already helped a couple conceive after 18 years of failed treatments, according to reporting on the first pregnancy achieved with the technology.
STAR stands for Sperm Tracking and Recovery. It combines high-speed imaging, machine learning and microfluidics to find and gently extract the rare sperm cells that standard laboratory methods miss in men diagnosed with azoospermia, meaning no sperm can be detected in a semen sample using conventional testing.
What azoospermia means for men trying to conceive
Azoospermia is not rare. The condition affects roughly 10 to 15 percent of men with infertility, according to Columbia Medicine magazine. For those men, the standard options have been donor sperm, adoption or invasive surgical retrieval, and none of them guarantee a biological child.
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Infertility as a whole is common. The World Health Organization estimates that around 17.5 percent of the adult population, roughly 1 in 6 worldwide, experience infertility at some point in their lives.
"With our method, many men who were previously told they have no chance of having a biological child now have that chance," said Zev Williams, the Wendy D. Havens Associate Professor of Women's Health and director of Columbia University Fertility Center, in a statement from Columbia.
How the AI actually finds the sperm
The core problem is scale. A semen sample from a man with azoospermia can look like a featureless soup under the microscope, with the handful of viable sperm outnumbered millions to one by cellular debris. Sifting through it by hand is slow and often futile.
STAR was built to solve that. High-speed cameras attached to a microscope capture more than 8 million images of a sample in under an hour, according to Columbia's clinical announcement. A machine-learning algorithm scans those frames for the tell-tale shape of a sperm cell.
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When one is found, the sample is routed through a microfluidic chip with channels as thin as a human hair, and a robotic system isolates the individual cell within milliseconds. Because the process avoids centrifugation, the fragile cells are not damaged in the recovery.
The speed difference over manual searching is the whole point. In one case reported by Interesting Engineering, two skilled technicians spent two days searching a sample by hand and found nothing. STAR processed the same sample in about an hour and located 44 sperm.
The first pregnancy, after 18 years
The first pregnancy achieved with STAR belongs to a couple who had pursued fertility treatment across multiple countries for 18 years without success, according to Interesting Engineering's account of the case. In March 2025, STAR identified three viable sperm in the husband's sample. Those cells were used to fertilize an egg, and an embryo was implanted.
The woman, identified by the pseudonym Rosie, gave birth to a healthy baby girl in December 2025, according to later reporting on the case.
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The method builds on imaging techniques originally designed to detect faint objects in space. "We're using the same technologies that are used to search for life in the universe to help create new life right here on earth," Williams said in the same reporting.
What it means for couples right now
STAR is still early. It has been used in only a small number of cases, is currently offered only at Columbia and costs about $3,000 per recovery attempt. Larger clinical evaluation is ongoing, and no long-term outcome data yet exists on the children born from the technique.
Even so, the technology has already earned formal recognition. STAR was named one of TIME's Best Inventions of 2025, and Columbia University Fertility Center was ranked first on Newsweek's America's Best Fertility Clinics list for the same year, according to Columbia Medicine.
For men facing a diagnosis of azoospermia, the practical advice has not changed. Anyone weighing a fertility workup, a second opinion or the option of experimental recovery methods should discuss it with a reproductive endocrinologist who can evaluate the specific cause and the realistic odds.
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