About SCSA
Physicians, laboratory directors and patients will immediately recognize the value of the Sperm Chromatin Structure Assay (SCSA®) test because it is a relatively inexpensive and statistically predictive measure of male infertility. The SCSA® test assesses DNA fragmentation using established methods that are supported by 25 years of research published in peer reviewed journals. These and ongoing studies indicate that sperm with elevated DNA fragmentation, as measured by the SCSA® test, have a lower probability of supporting a successful pregnancy.
The SCSA® test provides objective and statistically robust data that are relatively independent of standard semen measures and clearly show that motile, morphologically normal sperm may have extensive DNA fragmentation. The DNA Fragmentation Index (DFI) has been developed using SCSA® test data and is expressed as the percentage of sperm in a sample with elevated levels of DNA fragmentation. The statistically significant threshold for sub/infertility has been established at >30% DFI. Exceeding this threshold does not preclude normal fertilization, early embryo development and a full term successful pregnancy, but is associated in various clinical studies with a significant reduction in term pregnancies and an approximate doubling of miscarriages.
The SCSA® test is the only DNA fragmentation test that identifies the percent of immature sperm. Data from two large studies show that if the % of these sperm [termed High DNA Stainable (HDS) sperm]is >15%, there is an observed longer time to natural pregnancy or a reduced fertilization rate with routine IVF. ICSI may overcome this factor.
DNA fragmentation in sperm may be the result of many factors including, but not limited to disease, diet, drug use, high fever, elevated testicular temperature, air pollution, cigarette smoking and advanced age. With the exception of age, exposure to these factors may be transient and the resulting elevated level of DNA fragmentation may improve over time. DNA fragmentation levels also fluctuate in a small percentage of infertile men that have no known exposure to the aforementioned factors. However, in general, SCSA® test results are significantly more stable than standard semen measures of count, motility and morphology.
With a physician’s signature, patients may easily obtain the SCSA® test by preparing and shipping a small amount (0.2 - 0.4 ml) of a frozen semen sample to SCSA® Diagnostics, Inc. for analysis and interpretation. This may be done either at a clinic or via a home collection kit. SCSA® data may allow infertile couples to better understand the role of male factor infertility in their specific cases and weigh this information in their decisions regarding ART, including changes in lifestyle and nutrition, that may significantly reduce the level of sperm DNA fragmentation.
Note that we state a "reliable measure of male infertility" and not a "reliable measure of fertility". This is because male infertility may be a consequence of many factors, e.g. sperm density and motility, morphology etc. However, if a semen sample contains >30% of sperm with a high level of DNA fragmentation, this factor alone will statistically reduce the probability of a successful pregnancy. Data show that this is especially true for in vivo (natural intercourse), intrauterine insemination and routine IVF; other data suggest that the use of ICSI helps increase the statistical odds. However, given the higher costs of ICSI and other potential arguments against it, the SCSA® test can help guide the patient/physician on which methods would have the greatest benefit/cost.