In a nutshell
This article reviewed currently published data concerning the efficacy and safety of the different sperm retrieval techniques for men with reduced sperm production.
Around 10% of infertile men suffer from non-obstructive azoospermia, which describes a condition in which very few sperm cells are produced in the testicles – not enough to reach the ejaculated semen. In these cases, sperm should be retrieved directly from the testicles. The only way to obtain sperm cells for in-vitro fertilization (IVF – the artificial matching of eggs and sperm cells in a laboratory dish) in these men is via surgical procedures. There are currently three main techniques used for sperm retrieval:
- Testicular sperm extraction (TESE) involves the retrieval of sperm by surgically sampling small bits of testicular tissue
- Microdissection (MD) TESE is a modified TESE procedure, performed using a microscope to operate on the tiny structures inside the testicles
- Fine needle testicular aspiration (FNA) involves the retrieval of testicular tissue using a tiny needle
Methods & findings
The present article highlighted current research data concerning the outcomes of retrieving sperm cells from the testicles using TESE, MD TESE or FNA.
The authors found that TESE in which several samples were collected instead of a single sample offered better sperm retrieval rates (SRR). TESE is the most commonly used technique for testicular sperm retrieval and typically yields a SRR of around 50% in non-obstructive azoospermia. MD TESE was found to be equally effective as standard TESE in most cases, but requires special surgical training and takes longer to perform. Improved SRR were obtained using MD TESE coupled with a Doppler ultrasound of the testicles to uncover areas that were more likely to harbor live sperm cells. FNA is the least invasive technique, but generally the number of sperm cells retrieved is very small.
In terms of safety, the authors found that MD TESE is currently considered to be the safest technique, followed by FNA. Possible complications following sperm cell retrieval include bleeding, the formation of scar tissue and decreased levels of testosterone (the main male sex hormone) which may worsen infertility issues.
There are currently no conclusive studies comparing pregnancy rates between the three accepted sperm retrieval techniques.
The bottom line
Sperm cells can be retrieved from the testicles in men with non-obstructive azoospermia using three main techniques: TESE, MD TESE and FNA. Of the three, TESE and MD TESE are the most effective while MD TESE and FNA are safer. MD TESE is a more complex procedure not available in all centers.
If you are suffering from non-obstructive azoospermia, discuss sperm cell retrieval techniques with your doctor to determine which would be appropriate in your case.
Published By :
Human Reproduction Update
Feb 20, 2008