Where non-obstructive azoospermia treatment is heading
Non-obstructive azoospermia · Updated Nov 12, 2026
Surgery to search the testis for sperm finds some in about half of men. When it finds none, nothing is proven to restart sperm production. Research is aimed first at finding rarer sperm, and later at restoring or making it.
- 8trials open or running
- 181papers published in 2026
- 13NIH-funded projects
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Now
Nov 2026
Surgery finds sperm in about halfHappened 40–60% have sperm found
Micro-TESE, a search of the testis under a microscope, is the standard. Counting every couple who starts, about 1 in 4 ends with a baby or ongoing pregnancy from the man's own sperm.
40–60%: of men have sperm found at micro-TESE.
AI found sperm technicians missedHappened 1st pregnancy one couple
Columbia's STAR system led to the first pregnancy from AI-guided sperm search. One couple so far in published reports.
1st pregnancy: the first reported with AI-guided sperm search.
First sperm stem cell transplantHappened
A childhood cancer survivor received his own frozen sperm stem cells in Pittsburgh. Whether he is making sperm is not yet known.
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6 months
by May 2027
Stanford PRP pilot finishesPossible 16–28% had sperm found, uncontrolled
Ten men given platelet-rich plasma injections into the testis. Earlier reports had no comparison group.
16–28%: had sperm found after earlier failed surgery, with no comparison group.
Danish tissue-grafting study reportsPossible
Five healthy volunteers had their own frozen testis tissue grafted back under the skin, to see whether thawed tissue can still make sperm.
Data behind a lab-grown sperm claimLong shot
A startup said in April 2026 that it grew working human sperm in a dish. Peer-reviewed evidence would be the first of its kind.
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12 months
by Nov 2027
More AI sperm-search resultsPossible
A Brigham and Women's trial of an AI microwell system finishes, and Columbia's method should report outcomes beyond one couple.
New hormone-blocking pill reportsPossible
Leflutrozole, a drug that lowers estrogen to push testosterone and FSH up, tested in 15 men in Denmark.
Large hormone trial reads outLong shot About 2x odds of finding sperm, weak data
An 860-man randomized trial of hCG plus FSH before surgery. It had not opened when last updated, so its registered date looks optimistic.
About 2x: the odds of finding sperm in earlier low-quality studies.
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3 years
by late 2029
AI sperm search at major centersPossible
Automated searching of semen and tissue samples becomes a normal step before telling a man no sperm was found.
A test predicts if surgery will workPossible
Two NIH-funded efforts aim to tell men beforehand whether surgery is likely to find sperm, from semen or a small sample.
Sperm confirmed after a transplantLong shot
The Pittsburgh trial runs through 2029. Proof that transplanted stem cells make sperm in a person would be a first.
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5 years
by late 2031
A genetic cause found for most menPossible
Large sequencing studies are naming the genes behind individual cases, which decides who could benefit from gene-specific treatment.
First human trial of mRNA therapyLong shot 55% of tubules reached, mice
For men with a single faulty gene. It restored sperm and fertility in mice without altering DNA.
55%: of sperm-making tubules took up the mRNA in mice.
Working human sperm made in the labLong shot
Confirmed, peer-reviewed sperm from stem cells. Today the science reaches only the earliest sperm-forming cells.
The research paths
Finding sperm that is already there
1st pregnancy with AI sperm searchDetails and 1 trialsHide
Some men told they have no sperm have a handful that people cannot find by eye. AI imaging and microfluidic chips search millions of frames or cells to pull them out.
WatchPublished success rates across many men, not single cases.
Hormones and pills before surgery
About 2x odds of finding sperm, weak dataDetails and 2 trialsHide
Raising FSH and testosterone inside the testis might coax out more sperm before surgery. Past studies were small and biased. Randomized trials are now registered.
WatchWhether men with already-high FSH, the majority, benefit at all.
Injections into the testis
16–28% had sperm found, uncontrolledDetails and 2 trialsHide
Platelet-rich plasma and bone-marrow stem cells are offered at some clinics, often for a fee. No randomized trial shows either works, and repeat surgery alone finds sperm in some men.
WatchAny trial with an untreated comparison group.
Transplanting stem cells and tissue
Details and 3 trialsHide
Putting a man's own frozen sperm stem cells or testis tissue back. Built for childhood cancer survivors who banked tissue. It proves the techniques that lab-grown cells would later need.
WatchThe first confirmed sperm in a transplanted patient.
mRNA and gene therapy
55% of tubules reached, miceDetailsHide
For men whose azoospermia traces to one faulty gene. Delivering that gene's mRNA restored sperm and fertility in mice, with no change to DNA.
WatchA second gene treated the same way, and safety work in larger animals.
Making sperm in the lab
Details and 1 trialsHide
Turning skin or blood cells into sperm would help men with no sperm-forming cells at all. In 2026 researchers reached the earliest sperm-forming cells. Working human sperm has not been shown in peer-reviewed work.
WatchRemoving the mouse cells the method depends on, and monkey births.
Borrowed from other fields
From Computer vision
AI image search
First pregnancy
Scanning millions of images for a rare object, applied to finding a few sperm in a sample.
From mRNA vaccines
mRNA in lipid nanoparticles
55% of tubules reached
Mice
The vaccine delivery method, used to supply a missing gene's instructions to the testis for a few days.
From Childhood cancer care
Sperm stem cell transplant
First patient
Developed so boys can bank tissue before chemotherapy and get it back as adults.
From Breast cancer drugs
Leflutrozole
Phase 1/2
An aromatase inhibitor, the drug class used in breast cancer, lowers estrogen so the body raises testosterone and FSH.
From Acne treatment
Isotretinoin
44% had detectable sperm
Small studies
A vitamin A drug. Vitamin A signalling is needed to start sperm maturation.
From Sports medicine
Platelet-rich plasma
16–28% had sperm found, uncontrolled
Unproven
Concentrated growth factors from the man's own blood, injected into the testis.
From Stem cell biology
Stem-cell-made sperm cells
Lab
The method that produced mouse pups from lab-made sperm, now reaching the earliest human sperm-forming cells.
From Treatment of pituitary hormone deficiency
Hormone injections
About 2x odds of finding sperm, weak data
Randomized trial
hCG and FSH restore sperm in men who lack those hormones. The question is whether they help men who do not.
Open to join now
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Having micro-TESE
AI microwell system to find rare sperm
Locations and eligibility → -
Non-obstructive azoospermia
Platelet-rich plasma injection
Locations and eligibility → -
Anyone with the diagnosis
NIH study of genetic causes
Locations and eligibility → -
Banked tissue before treatment
Stem cell transplant and tissue grafting
Locations and eligibility → -
Banked tissue as a child
Immature testis tissue transplant
Locations and eligibility →
See every recruiting azoospermia trial →
When the trials finish
Completion dates the trials registered. Results usually follow 3 to 12 months later.
- Heating up
- Maturing
- Early
- Cooling
- Fully enrolled, waiting on results
- Still enrolling
Knowledge on the way
Not treatments yet: detection, causes and how care is delivered. Mostly NIH-funded.
- AreaQuestionFunded throughNews likely
- Causes A national center mapping the genes behind male infertilityMagee-Womens Research Institute · NIH Funded through Jun 2028 News likely 2027–2028
- Causes Genomics of impaired sperm productionOregon Health & Science University · NIH Funded through Jun 2027 News likely 2027–2028
- Causes Genome study of 500 people with azoospermia or early ovarian failureNIH (NICHD) · recruiting Funded through Jan 2031 News likely 2029–2031
- Detection A non-invasive test for whether surgery will find spermUC San Diego · NIH Funded through Jun 2028 News likely 2028
- Detection An epigenetic test for severe sperm-production failureInherent Biosciences · NIH small-business grant Funded through Aug 2028 News likely 2027–2028
- Care Deep-learning microwell system to screen for rare spermBrigham and Women's · NIH Funded through Apr 2029 News likely 2027–2029
- Biology Sperm stem cell transplantation and culture in patientsMagee-Womens Research Institute · NIH Funded through May 2030 News likely 2028–2030
- Biology Mapping the human sperm stem cell's home in the testisUT Southwestern · NIH Funded through Jan 2029 News likely 2027–2029
- Risk DNA repair faults in infertile men and their cancer riskChildren's Mercy Kansas City · NIH Funded through Apr 2029 News likely 2027–2029
- Biology Gene therapy for faulty support cells, in animalsUniversity of Pittsburgh · NIH fellowship Funded through Feb 2027 News likely 2027
What just happened
Early sperm-forming cells made from human stem cells
Published in Cell Stem Cell. Still depends on mouse testis cells and does not produce working sperm.
A startup claimed working human sperm grown in a dish
A company announcement, not yet peer reviewed or independently confirmed.
ASRM: lab-made sperm and eggs not ready for use
The ethics committee says use for reproduction should wait for reassuring monkey studies.
mRNA injection restored fertility in mice
One injection into the testis, sperm within three weeks, healthy pups, no DNA changes.
First pregnancy from AI-guided sperm search
Columbia's STAR system, described in a Lancet letter. One couple.
First sperm stem cell transplant reported
Done in November 2023 in Pittsburgh. Safe; outcome not yet known.
Standard treatment today
- Finding the causeTwo semen tests, hormone levels, a chromosome test and a Y-chromosome deletion test. Some deletions mean surgery will not find sperm.
- Getting spermMicro-TESE surgery, with any sperm found used for IVF by injecting one sperm into each egg.
- Hormones before surgeryUsed for selected men, mainly those with low testosterone. Not routine, because the evidence is weak.
- When no sperm is foundDonor sperm or adoption. No treatment is proven to restart sperm production.
How to read this page, and sourcesHow to read this page, and sources
- Several items rest on one patient or on mice. They show something is possible, not how often it works.
- Stem cell and platelet-rich plasma injections are sold by some clinics. No controlled trial supports them.
- Completion dates are what each study registered. Small single-site studies often run late.
- "News likely" for NIH projects is our estimate from each grant's end date.
- Forecasts are editorial judgments by Find a Trial, not predictions from researchers or regulators.
See azoospermia trials recruiting now →