Sperm DNA fragmentation test (SCD)

SCD test helps detect increased fragmentation of genetic material in sperm

Sperm DNA fragmentation test (SCD)

Fragmentation of sperm DNA can be one of the main causes of reduced male fertility. It can also cause abnormalities in early embryo development, resulting in miscarriage. You will investigate it with the SCD test.

SCD study

There are many methods to assess the degree of sperm DNA fragmentation. The two most popular methods are the SCD test and the SCSA test. At Invimed Clinics, we use the SCD (Sperm Chromatin Dispersion) test, or sperm nuclear chromatin dispersion test, to assess sperm DNA fragmentation.

Fragmentation of sperm DNA

Spermatozoa with properly condensed sperm chromatin have adequately protected DNA from damaging factors such as oxidative stress. When sperm DNA is exposed to these factors, DNA integrity can be compromised and fragmentation can occur. 

Fragmentation of sperm DNA

Spermatozoa with properly condensed sperm chromatin have adequately protected DNA from damaging factors such as oxidative stress. When sperm DNA is exposed to these factors, DNA integrity can be compromised and fragmentation can occur. 

The result of fertilisation of an ovum with a sperm with sperm chromatin fragmentation can be:

  • abnormal early embryonic development,

  • implantation deficiencies,

  • recurrent miscarriages,

  • increased risk of genetic defects in the offspring.

Result of SCD

The result of the sperm chromatin dispersion test is the so-called SDF index - Sperm DNA Fragmentation:

  • SDF ≤ 25% - normal result,

  • SDF ≥ 25% - abnormal result.

The result of the study is usually ready within 15 working days; up to a maximum of 21 working days.

When to perform an SCD?

Evaluation of sperm DNA fragmentation is recommended as an adjunct to male infertility diagnosis.

Performing an SCD is particularly recommended if the partner is present habitual miscarriages. More than half of recurrent miscarriages are associated with fetal genetic defects. One genetic factor on the male side that causes recurrent miscarriages is sperm DNA fragmentation.

The cause of DNA fragmentation can be oxidative stress, as well as damaged sperm chromatin repair mechanisms. Damaged sperm DNA is responsible for microdeletions and double-strand breaks in chromosomes. Scientific studies have shown correlations between sperm DNA fragmentation and blocked embryo development, resulting in spontaneous abortion. Sperm with DNA fragmentation also increases embryo implantation failure.

The test should be performed in the following cases:

  • recurrent miscarriages,

  • infertility of unknown cause (idiopathic),

  • in men over 40 years of age, even if they have previously had children,

  • semen examination showed significantly reduced parameters, especially in sperm morphology,

  • in cases of exposure to toxic substances and factors that increase the risk of DNA damage (smoking, varicocele, factors that increase the temperature in the scrotum, obesity, diabetes, chemotherapy and radiotherapy),

  • repeated failure of embryo implantation in IVF procedures,

  • when there is an indication for in vitro oocyte fertilisation by ICSI/IMSI,