The two types of azoospermia
- Obstructive
- Sperm production is normal, but there is a blockage along the way, caused by a previous vasectomy, congenital absence of the vas deferens, infection or prior surgery. The sperm are there; the problem is transport.
- Non-obstructive
- Sperm production inside the testicle is impaired, because of a genetic or hormonal cause, previous chemotherapy, or no identifiable cause. In this case there may be isolated pockets of sperm production scattered among inactive tissue, and the challenge is finding them.
The two types are told apart through physical examination, hormone levels (especially FSH), testicular volume and, when indicated, genetic testing. See how a male infertility workup works.
The techniques
- PESA
- Percutaneous epididymal sperm aspiration. A simple procedure done with a needle, indicated for obstructive azoospermia. It has a high success rate in this setting, and recovery is quick.
- TESA
- Testicular sperm aspiration, also done with a needle. It is used when aspiration from the epididymis is not feasible or fails to retrieve sperm.
- TESE
- Testicular sperm extraction: a biopsy removes testicular tissue, which is then searched for sperm. It is used in obstructive azoospermia when needle procedures are not feasible, and in selected cases of non-obstructive azoospermia.
- Micro-TESE
- Microdissection testicular sperm extraction, performed with an operating microscope. The microscope makes it possible to identify the most dilated seminiferous tubules, which are the most likely to contain sperm. This increases the chance of finding sperm and reduces the amount of tissue removed, helping preserve testicular function. It is the technique indicated for non-obstructive azoospermia, and the one that requires the most specialized training.
The realistic chances
In obstructive azoospermia, sperm retrieval succeeds in the vast majority of cases.
Non-obstructive azoospermia is different, and this needs to be said up front: micro-TESE does not guarantee that viable sperm will be found. Success rates vary with the underlying cause, the hormonal profile and the patient's history, and some procedures do not retrieve usable sperm. That is why the evaluation beforehand is so detailed. Its purpose is to estimate the chances in your specific case, not to give a generic answer.
Retrieving sperm is also not the same as achieving a pregnancy. The retrieved sperm are used for IVF, and its outcome depends on other factors, including the female partner's evaluation.
What the procedure involves
It is performed under anesthesia, and the tissue is processed by a fertility lab at the same time, which requires advance coordination with the assisted reproduction team. The sperm can be frozen for later use, or the procedure can be timed to match the female partner's cycle.
Recovery is quick, with a return to usual activities within a few days. The procedure is not risk-free, however. Besides the usual risks of surgery, some patients may develop transient hypogonadism, a temporary drop in testosterone production, which is monitored as part of postoperative follow-up.
Evaluation
Choosing the right technique requires a complete evaluation. The first consultation and a review of the tests you already have can be done by telemedicine.
Frequently asked questions
Does azoospermia mean I'm infertile?
Not necessarily. It means there are no sperm in the ejaculate. In many cases the testicles are still producing sperm, and retrieval techniques make biological fatherhood possible through assisted reproduction.
What is the difference between TESE and micro-TESE?
Micro-TESE uses an operating microscope to find the tubules most likely to contain sperm. This increases the chance of finding sperm in non-obstructive azoospermia and removes less tissue, better preserving testicular function.
Does micro-TESE always find sperm?
No. In non-obstructive azoospermia, some procedures do not retrieve viable sperm. The rate varies with the cause and the hormonal profile, and the evaluation beforehand exists precisely to estimate that chance before you decide.
I've had a vasectomy. Do I need micro-TESE?
Probably not. For azoospermia after a vasectomy, there are two routes: surgical reversal, or needle sperm retrieval combined with assisted reproduction. The choice depends on how long ago the vasectomy was done and on the couple's plans.
