Azoospermia is the term that’s used when a standard semen analysis finds no sperm in the ejaculate. However, a revolutionary new procedure, the Extended Sperm Search & Microfreeze (ESSM), finds and freezes small numbers of sperm in 44% of men with azoospermia. This groundbreaking lab test is performed by dividing the entire semen sample into 5 micro-liter droplets and carefully scanning the drops under a high-powered microscope. Any sperm located are placed on a specialized device, called SpermVD, and cryopreserved for use in intracytoplasmic sperm injection (ICSI-IVF).

The SpermVD’s innovative design allows individual sperm to be transferred to a microdroplet for freezing. Because the sperm are successfully frozen in such a small quantity of fluid, over 90% of them survive the freeze and thaw process, and also makes them easily found when thawed on the day they are needed to inject into their partner’s egg (ICSI).  

  • This makes it much more likely that sperm will be found than when the sperm are frozen in conventional vials.
  • This makes finding sperm faster, so that they can be injected as soon as possible after the eggs have been retrieved from his partner, which optimizes fertilization and pregnancy outcome rates.

“Using the device was easy… Knowing that there are sperm and that most will survive really takes stress off the lab. The saved time is relieving on a very busy day.”
- Reproductive Specialists of New York

This procedure was introduced to us by Mordechai Koenig of ATIME who has been tireless in his patient advocacy and in his commitment to bring this procedure to the U.S. and to our attention. As a result, Maze is currently the only laboratory in the U.S. offering this procedure. 


If you’ve been diagnosed with one of the following, you may be a candidate for ESSM:

  • Azoospermia: no sperm observed in the ejaculate in a conventional semen analysis; 44% of azoospermic men will have sperm found and successfully frozen
  • Cryptozoospermia: where only a very few sperm can be found, even after centrifuging and concentrating the specimen; almost all of these men will have a successful ESSM and be able to proceed with IVF/ICSI.
  • Severe Oligozoospermia: sperm concentration less than 1 million/mL

Dr. Michael Werner, Maze Lab Director and a fellowship trained urologist specializing in male infertility, feels strongly that every man with the diagnosis of azoospermia or cryptospermia should undergo an ESSM prior to considering sperm mapping or testicular sperm extraction (micro-TESE). ESSM is non-invasive and may be performed as many times as needed. The surgical extraction procedures are invasive and may cause some damage to the testicles. 

However, if the ESSM does not find sperm, sperm mapping followed by micro-TESE (if areas of sperm production are found on the sperm mapping) is a viable option and should be strongly considered.

Patient Testimonials

We were at the end of the road before we came to Maze...

We have been trying to conceive for over ten years now and honestly we were close to the end of the road before we came to Maze. I have done sperm analysis’s over fifteen times in four different countries. All with the same disappointing result; azoospermia. After every test I took I would wish for at least one sperm to be found just as a sign of hope but I was always told there is nothing. I have been to the top urologist in this country and their only solution would be a surgery. My wife and I were against the surgery unless we have exhausted all other options.

I say faith brought us to you. I did the test in the morning in Manhattan and was expecting a call the next day or two as usual with the usual disappointing news of azoospermia. I remember getting a call later that evening from a New York number and did not even think it was you. I answered that call that changed our life for the better. I remember you telling me that, “I have good news for you we were able to freeze over 40 sperm.” and I could not believe my ears. I remember asking you if you’re sure you called the right person!!! It was the greatest news I had ever received in my life to say the least. I did a few more tests with positive results to ensure we have enough just as a safety net even though you told me it’s enough to conceive.

I’m glad to announce that this year we had a beautiful baby boy after a few failed IVF procedures who is the center of our lives now. I ultimately hope that you are able reach as many people as possible with your innovative techniques and dedication to your skills. Your emotional support was beyond what we expected and much appreciated. This is only a fraction of our gratitude for you and your facility for everything you have done for my family.
Thank you from the bottom of our hearts…

FK, 37

ESSM test finds sperm in azoospermic patient, yielding 7 healthy embryos.

“I was told I was azoospermic after going to several well-known fertility centers in the tri-state area. I then came to Maze Laboratories for a standard semen analysis, which also showed zero sperm count. However, after having Maze’s ESSM lab test, 42 sperm were recovered and safely stored. In collaboration with the IVF lab, my wife and I are happy to say that 7 healthy embryos were developed!”

– J, 37 –

Notable Publications

  1. Dr. Michael Werner shares background & results for Extended Sperm Search & Microfreeze, with A Time. (March 2021) Read Article
  2. Fertility Outcomes – Extended Sperm Search
  3. Microfreeze- A Novel solution for freezing small numbers of spermatozoa


If you believe you're an appropriate candidate for the ESSM procedure, we encourage you to contact us as soon as possible. A phone consultation will be conducted to discuss the procedure in detail, answer any questions you may have and schedule the appointment. You will then be required to send your records to Dr. Werner for review.

* The Extended Search procedure, which was developed and is performed in Israel by MFC Labs, is exclusively performed in the U.S. by Maze Health. Special thanks to Mordechai Koenig, and ATIME for notifying us about this groundbreaking technique.

Last Updated: June 2022