Sperm DNA fragmentation refers to damage in the genetic material (DNA) of the sperm. Here we’ll explore what it is, how it’s measured and how it can be treated. 

What is sperm DNA fragmentation?

Sperm DNA fragmentation is when the DNA within the head of the sperm is damaged (fragmented). The damage is not known to have an impact on the fertilisation of eggs, however, high levels of sperm DNA fragmentation may negatively affect embryo development, implantation and pregnancy

What are the causes of sperm DNA fragmentation?

Sperm DNA fragmentation can occur during sperm production, sperm maturation or from external factors like oxidative stress (a condition caused by low levels of antioxidants). This in turn can be caused by inflammation or infections in the male genitals (like sexually transmitted diseases), varicoceles (enlarged blood vessels in the testicle), environmental and lifestyle factors, smoking and recreational drug use. 

How do you test for sperm DNA fragmentation?

Testing for sperm DNA fragmentation is a non-invasive procedure performed as an additional diagnostic tool and is not included in the standard semen analysis. There are no risks involved in testing as it uses a small sample of sperm that would not be used for treatment. Several different methods are available for assessing sperm DNA fragmentation and the results should be discussed with your clinician in order to understand if they are within normal range. 

When might the test be offered?

Sperm DNA fragmentation may be offered in cases of unexplained infertility or recurrent miscarriages. It may also be offered following a fertility treatment if there has been poor fertilisation, poor embryo development or after multiple cycles of IVF if you have not fallen pregnant. 

How can you treat sperm DNA fragmentation?

Changes to lifestyle is one of the most fundamental and simple ways to improve sperm quality and DNA damage. Men with low semen quality and high DNA fragmentation are recommended to quit smoking, reduce alcohol consumption, exercise and manage their weight. If an infection is present, it should be treated with a course of antibiotics and if varicoceles are the cause, then these can be surgically repaired. A common treatment that may be offered is an oral antioxidant therapy, however, currently, there is little evidence to support if oral antioxidants can repair DNA damage or increase the chances of having a baby.