Sperm Chromatin Structure Assay (SCSA)
Definition - What does Sperm Chromatin Structure Assay (SCSA) mean?
Sperm chromatin structure assay (SCSA) is a test that assesses the vulnerability of the sperm’s genetic material (DNA) to acid-induced DNA fragmentation, which is the disruption of the hydrogen bonds between the DNA strands. Chromatin makes up the genetic material and is contained within the head of the sperm. A higher degree of DNA fragmentation indicates that the sperm lacks fertility potential. While the SCSA serves as a tool for determining a man’s fertility capability, it also helps predict successful pregnancy in couples who are planning pregnancy for the first time as well as in couples undergoing intrauterine insemination. It also assists couples who have a history of repeated, unexplained miscarriages; increased sperm DNA damage may account for the increased rate of miscarriages.
FertilitySmarts explains Sperm Chromatin Structure Assay (SCSA)
To evaluate the DNA breaks in SCSA, the sperm DNA is exposed to acid. The acid will cause the susceptible or abnormal DNA to break or fragment. The DNA fragmentation is then assessed with the help of flow cytometry – a technology that analyzes the characteristics of cells as they move in a fluid stream through a beam of light.
SCSA follows a strict protocol and utilizes a dedicated software to analyze the flow cytometric results. The percentages of red and green sperm are plotted using the SCSA software. An increased percentage of red sperm called as the DNA fragmentation index (DFI), indicates impaired fertility potential.
DFI is an excellent predictor of male infertility. The greater the DFI, greater are the chances of male infertility. Lower levels of DFI are associated with higher chances of pregnancy, including both spontaneous pregnancy or that achieved via in vitro fertilization (IVF) and intrauterine insemination (IUI).