Sperm DNA fragmentation is a test that assesses the level of DNA damage within sperm. It is a variable independent to the parameters measure in a routine semen analysis (such as motility and morphology). Research suggests that sperm carrying high levels of DNA damage are less likely to produce successful pregnancy.

 

Interestingly, people with an otherwise normal semen analyses can have a high degree of DNA damage and those with very poor sperm quality can have very little DNA damage. Importantly, the degree of DNA fragmentation strongly correlates with the inability of the sperm to initiate fertilisation and even if fertilisation occurs, high DNA fragmentation will often result in arrested embryo development before implantation. Research also shows that even if a pregnancy is achieved from sperm with high levels of DNA fragmentation, there is a significantly higher likelihood that it will result in miscarriage.

 

Causes of Sperm DNA Fragmentation

In men, the major contributing factor for sperm DNA fragmentation is oxidative stress, which can be associated with one or more of the following:     

• Infection      

• Pyrexia     

• Elevated testicular temperature     

• Recreational drugs     

• Smoking     

• Alcohol     

• Stress     

• Diet     

• Environmental and occupational pollutants     

• Advanced chronological age     

• Varicocele

 

Indications for men who may benefit from the sperm fragmentation  test:     

• Unexplained infertility     

• Arrested embryo development     

• Poor blastocyst development     

• Multiple failed IVF/ICSI treatments     

• Recurrent miscarriage   

• Advanced chronological age        

• Varicocele     

• Poor semen parameters   

• Exposure to harmful substances

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Treatment of high sperm DNA fragmentation

Treatment depends on the cause of DNA fragmentation. If the damage is caused by free radicals, a change in lifestyle and diet designed to protect against oxidative stress may help reduce the levels of DNA fragmentation.

 

Other treatment options include:     

• Antibiotics in the co-existence of an infection   

• Life style changes – drugs, smoking and occupation     

• Diet – fresh foods, particularly those containing antioxidants and vitamin C & E     

• Varicocele surgery     

• Testicular aspiration of sperm (DNA damage occurs at the post-testicular level, hence testicular sperm may have a better DNA integrity than ejaculated sperm)