Sperm DNA fragmentation
High sperm DNA fragmentation (SDF) is associated with reduced natural pregnancy rates and assisted conception pregnancy rates as well as live birth rates. Sperm DNA fragmentation also leads to higher miscarriage rates, as published in the ESHRE Recurrent Pregnancy Loss 2017 Guideline. High levels of DNA fragmentation may be reduced by considering varicocele repair, treatment of underlying infections or inflammation, changes in lifestyle, or with antioxidant supplements. Sperm DNA can be damaged when sperm are being made in the testes or as they mature before ejaculation. This damage breaks the DNA into fragments, so sperm DNA tests are also known as sperm DNA fragmentation tests. Men with high levels of sperm DNA damage are less likely to get their partner pregnant and have increased risk of miscarriage and/or ART failure. Even if semen analysis results are ‘normal’, the sperm DNA could be damaged and therefore poor quality.
When requesting Sperm DNA Fragmentation there are two options. Please specify whether the request is for sperm DNA fragmentation by SpermComet or SCSA test.
Examen sperm DNA fragmentation (SDF) tests [CMET/CMT3 / CMT5] CHANGE
Powered by SpermComet® technology, Examen sperm DNA fragmentation (SDF) tests directly measure SDF damage within the sperm cell itself (i.e. unlike some other tests which measure only an indirect proxy for SDF damage).
Examen’s SDF tests provide one of the highest performance levels among commercially available SDF tests, directly measuring total single- and double-strand DNA breaks (CMET/CMT5), and also double-strand breaks only (CMT3/CMT5).
Use Examen’s SDF tests for:
- couples struggling to achieve pregnancy (idiopathic infertility), especially where a semen analysis was ‘normal’, or where IVF cycles did not progress due to pre-implantation failures (Exact® CMET /Extensiv CMT5)
- couples struggling to keep the pregnancy / suffering recurrent pregnancy loss, where
ART did not progress due to post-implantation failures, especially if multiple early losses
<14 weeks, and female age >35 (Extend® CMT3 / Extensiv CMT5)
Examen’s tests have the advantage of requiring only very low numbers of sperm (<10K) and so are suitable for men with very low sperm counts (oligozoospermia) and can also be used for surgically retrieved sperm samples. The clinician must select the desired test prior to sending the patient as well as ensuring completion of the Examen test request form.
Sperm Chromatin Structure Assay (SCSA type test) [SEXT]
The SCSA is a highly validated test that measures DNA fragmentation in sperm by analyzing large numbers of cells (typically between 5,000 and 15,000 sperm) rapidly from an ejaculate sample. It uses Acridine Orange flow cytometry to detect both single- and double-strand DNA breaks, based on changes in fluorescence. Developed over the past 35 years using both human and animal models, SCSA is one of the most statistically robust and reproducible methods for assessing sperm DNA integrity. It is a standardized, CE Marked test known for its high reproducibility and low variability.
A minimum sperm concentration of approximately 100,000/mL is required for accurate testing.
| Test name |
|---|
| Sperm Comet® |
| Sperm Comet® Exact Focus |
| Sperm Comet® Extend |
| Sperm Comet® Extend Focus |
| Sperm DNA Fragmentation (SCSA type test) |
Instructions for collection of Sperm DNA Fragmentation and Aneuploidy specimens
Sperm DNA Fragmentation or Sperm Aneuploidy testing are not part of the Comprehensive Semen Analysis and need to be requested as a separate test, test code SEXT, CMET / CMT3 / CMT5 and SPPL, respectively.
Semen samples ideally need to be frozen as soon as possible after liquefaction, but not longer than 60 minutes post ejaculation. Samples must be snap-frozen for Sperm DNA Fragmentation and cryopreserved in TYB for Sperm Aneuploidy.
If samples are prepared by another laboratory:
Two cryovials containing not less than 0.25 mls of semen is required. Frozen samples can be sent to, or collected by TDL, by arrangement, and must be accompanied with relevant patient details and the sperm count. For Examen SpermComet® SDF tests please ensure a completed Examen test request form accompanies the TDL request form.