Non-Obstructive Azoospermia: Diagnosis, Micro-TESE and the Possibility of Fatherhood
Being told that no sperm were found in your semen can be devastating, particularly when you are hoping to become a father. But azoospermia does not always mean that biological fatherhood is impossible. The first step is determining why sperm are absent and whether there may still be sperm that can be found and used in fertility treatment.
I am Dr. Philip Werthman, Director of the Center for Male Reproductive Medicine and Vasectomy Reversal in Los Angeles. For more than 35 years, I have helped couples navigate male infertility. One important focus of my practice is non-obstructive azoospermia, a condition in which sperm production within the testicles is severely reduced or absent.
Obstructive vs. Non-Obstructive Azoospermia
Azoospermia means that no sperm are detected in the ejaculate. There are two broad categories. In obstructive azoospermia, sperm are being produced but a blockage prevents them from reaching the semen. In non-obstructive azoospermia, the problem lies primarily in sperm production itself. These conditions require different approaches, so distinguishing between them is critical.
Why a Careful Evaluation Matters
My evaluation begins with a detailed medical history, physical examination, hormone testing, appropriate genetic testing, and at least two semen analyses performed with centrifugation. Repeating the test matters: occasionally, rare sperm are detected on a subsequent sample even when an earlier analysis showed none.
Not all laboratories evaluate semen in the same way. I recommend a fertility-focused laboratory experienced in examining the centrifuged specimen, which can help identify very small numbers of sperm that might otherwise be overlooked. Finding sperm in the ejaculate can sometimes change the treatment plan and may permit sperm freezing without surgery.
Sperm Production Is Not Always Uniform
Sperm are made inside tiny structures in the testicles called seminiferous tubules. They are microscopic tubes, and sperm production takes place within their walls. In men with non-obstructive azoospermia, production may be patchy: one area of the testicle may produce no sperm while another small area may still produce some.
This variation is central to the way I approach surgery. Under a high-powered operating microscope, seminiferous tubules can differ in appearance. Certain tubules may look more promising for sperm production than others, although appearance alone cannot guarantee that sperm are present. Careful microscopic inspection helps guide where I take tissue samples, rather than relying on random sampling alone.
My Mini-Incision Micro-TESE Technique
Micro-TESE stands for microsurgical testicular sperm extraction. I developed a mini-incision microsurgical approach that allows me to inspect and sample different regions of the testicle through a small incision, generally less than an inch long. The goal is to identify areas more likely to contain sperm while limiting unnecessary tissue removal and injury to the testicle.
An important difference is what happens inside the scrotum. In a conventional micro-TESE, the surgeon generally delivers the testicle out of the scrotum and makes a broad opening in its outer covering—sometimes described as opening it like a clam—to expose the seminiferous tubules. This provides extensive access, but the greater degree of exposure and dissection can disrupt blood vessels and healthy testicular tissue. A potential complication of testicular sperm extraction is reduced testosterone production, particularly in men whose testicular function is already impaired.
With my mini-incision technique, I keep the testicle inside the scrotum while working through a much smaller opening. Using the operating microscope, I inspect and selectively sample promising tubules from different regions while aiming to preserve the testicle’s blood supply and minimize trauma to healthy tissue. This approach is designed to reduce surgical disruption, but no testicular operation is entirely without risk, including the possibility of changes in testosterone levels.
The incision is so small that I generally do not even use a Band-Aid anymore. I simply close the area with a little surgical glue. The limited incision and dissection are also intended to make recovery easier. In my experience, patients often have relatively little postoperative discomfort and can return to work and ordinary daily activities sooner than they might expect after more extensive testicular surgery. Recovery varies, and strenuous exercise and heavy lifting still require appropriate restrictions.
In appropriately selected men treated in my practice, sperm are found in approximately 60% to 70% of cases. This is my clinical experience, not a guarantee for any individual patient; the likelihood of success depends on the underlying diagnosis, prior treatments, genetics, and other factors.
Why I Prefer One Procedure Rather Than Two
Some physicians recommend a separate diagnostic procedure, such as a testicular biopsy or sperm mapping, followed later by micro-TESE to retrieve sperm.
My philosophy is simple: Why perform two procedures when one can answer both questions?
I do not believe a separate diagnostic biopsy or sperm-mapping operation is necessary before micro-TESE. During the micro-TESE itself, I can assess whether sperm are being produced and, when found, retrieve them for IVF. My objective is to accomplish both in one operation, sparing patients a second procedure, another anesthetic, and another recovery.
What Happens if Sperm Are Found?
If viable sperm are recovered, they may be used in in vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI). With ICSI, an embryologist injects a single sperm directly into an egg. Embryos may then develop and, when successful, lead to pregnancy and the birth of a child. Sperm retrieval is only one step; the female partner’s fertility and the quality of the eggs and embryos also influence outcomes.
Timing Micro-TESE With IVF: Fresh or Frozen Sperm
Micro-TESE can be coordinated with a partner’s IVF cycle so that the retrieved sperm are used fresh. The procedure is often performed approximately two to four days before egg retrieval, although it may also be performed on the same day. Exact scheduling is coordinated with the IVF team and laboratory so viable sperm are available when the eggs are ready for ICSI.
Alternatively, micro-TESE can be performed well in advance of IVF. If sperm are found, they can be frozen and later thawed for ICSI when the couple is ready to proceed. This allows a couple to find out whether sperm are available before the female partner undergoes ovarian stimulation and egg retrieval.
Research has often shown similar clinical pregnancy outcomes using fresh and frozen-thawed testicular sperm, although results across studies are not completely uniform, and some recent analyses suggest fresh sperm may offer an advantage for certain outcomes. Frozen sperm remains a well-established option. When very few sperm are obtained, the likelihood of successful freezing and recovery after thawing is also an important consideration.
The timing is a personal decision. Some couples prefer to confirm that sperm have been retrieved and frozen before beginning IVF. Others prefer to coordinate micro-TESE with egg retrieval and use fresh sperm, with a backup plan—such as donor sperm or freezing retrieved eggs—if no usable sperm are found. We discuss these choices and coordinate closely with the reproductive endocrinologist and embryology laboratory before proceeding.
What if a Previous Sperm Retrieval Was Unsuccessful?
An unsuccessful biopsy or sperm retrieval elsewhere does not always close the door. In some cases, a repeat evaluation or carefully planned micro-TESE may still offer a chance to find sperm. The prior operative report, pathology, genetic testing, hormone levels, and overall reproductive goals all help determine whether another attempt is reasonable.
Experience, Precision and a Personalized Plan
Non-obstructive azoospermia is complex, and treatment should never be one-size-fits-all. My approach combines a careful diagnostic workup, targeted microsurgical evaluation of seminiferous tubules, and a commitment to preserving as much healthy testicular tissue as possible.
For over 35 years, I have helped thousands of couples address male infertility. If you have been diagnosed with azoospermia—or were told that no sperm could be found during a previous procedure—I would welcome the opportunity to review your situation and discuss your options.
Schedule a consultation with the Center for Male Reproductive Medicine and Vasectomy Reversal in Los Angeles to learn whether mini-incision micro-TESE may be appropriate for you.
