DNA Fragmentation Test

One kind of male fertility test that quantifies the quantity of damaged DNA in a sperm sample is called DNA fragmentation. The DNA is considered damaged when the strands or chains are broken. All men have some amounts of damage in their DNA, but higher percentages of damage may indicate greater difficulty in achieving and maintaining a pregnancy. The DNA fragmentation test may not be generally available, so it is recommended for couples to seek overseas medical treatment. This is usually made available by medical health travel agencies or meditour agencies. It can be a form of medical tourism or health tourism.

Why get a DNA fragmentation test?

DNA is the code of life. This means that if the sperm’s DNA is damaged, it reduces the chances of pregnancy and delivery of a healthy baby. Research has also shown that a high level of DNA fragmentation in sperm is associated with infertility, failure of IVF treatment cycles and early-term miscarriages.

Who should have a DNA fragmentation test?

The test is recommended for anyone who has had any of the following:

• Has been trying to conceive without success for a year or more
• Has suffered a miscarriage
• Considering starting IVF treatments
• Has had one or multiple failures with IVF

Understanding the reason for the test

The sperm carries DNA from the male testicles to the female egg. There is a very large amount of DNA that is compacted into each tiny sperm. This fragile DNA is tightly wrapped around protein structures which help in protecting it. Together, these protein structures and DNA form chromatin. Sperm chromatin is the most compact form of DNA and even with the protection, is still vulnerable to damage during the journey that starts with the production of sperm in the testicles and extends throughout the epididymis and vas deferens before it is ejaculated. Extensive DNA fragmentation is associated with infertility and miscarriage. It may also make both natural conception and conception with IUI more difficult. The causes of sperm DNA damage include:

• Environmental pollution
• Diet and lifestyle choice factors
• Infections
• Certain types of cancers
• Varicocele
• Excessive heat exposure

There is some degree of sperm DNA fragmentation that exists in all men, even in those with normal sperm analysis. DNA fragmentation has also been seen to increase with age, meaning that sperm DNA damage may be higher in older men. There has also been a link between sperm DNA damage with lower male fertility rates. However, the data is less clear when it comes to establishing the exact guidelines based on sperm DNA fragmentation testing.

What are the types of sperm DNA fragmentation tests?

Several testing methods exist in determining sperm DNA integrity and they include:

• TUNEL assay
• SCD (sperm chromatin dispersion test)
• SCSA (sperm chromatin structure analysis)
• COMET assay

The SCSA is the most widely studied DNA integrity test. For the test, sperm is introduced to a special dye, which helps to identify the damaged DNA. Men with normal semen analysis can have sperm DNA damage, just as it is possible for men with poor sperm quality to have relatively little sperm DNA damage. Fertility rates are lower in men with higher levels of sperm DNA fragmentation.

What does the DNA fragmentation test result look like?

After the tests, the fertility specialists will review the DNA fragmentation test results with the couple and then make the appropriate recommendations that will be based on the specific situation. However, some general guidelines help in highlighting the severity of DNA fragmentation and how it may impact fertility. Some of the basic guidelines for determining fertility potential are as follows:

• 15% or less fragmentation means that there is excellent sperm DNA integrity
• 15-25% DFI means the integrity is good to fair
• 25-50% DFI means the integrity is fair to poor
• 50% or greater DFI means the integrity is extremely poor

Also, some recent studies have shown that even with high DNA fragmentation rates, up to or more than 30%, pregnancy rates may still be comparable to those with excellent sperm DNA integrity when reproductive assistance techniques are used.

Comparing DNA fragmentation and sperm quality test

DNA fragmentation identifies chromosomal breaks and is recommended later in the fertility journey in cases of recurrent pregnancy loss. A sperm quality test (SpermQT) is a test that examines the abnormalities in the sperm gene function and is recommended in the initial stage of the fertility journey. While the DNA fragmentation test shows a break in the DNA chain, SpermQT results show genes that are disrupted due to lifestyle and environmental factors. These factors can include stress, alcohol consumption, toxins, smoking and more. 

SpermQT results highlight three levels of sperm quality ranked as excellent, normal or poor. Each result is also associated with pregnancy outcomes when a couple is trying intrauterine insemination (IUI) in trying to conceive. These results can then offer guidance on how to proceed for both the couple and the doctor. While there is conflicting data about how DNA fragmentation impacts fertility outcomes, studies have shown that the factors that are uncovered by SpermQT can be overcome by IVF and ICSI.

Are there any treatments for men with poor-quality sperm DNA?

Not all the factors or conditions that cause sperm DNA fragmentation can be effectively treated. However, when the damage is due to oxidative stress, diet and lifestyle changes may prove to help reverse it. In cases where the cause is infection from certain bacteria, treatment with antibiotics may be recommended. In cases of varicocele, the surgical repair of the condition may improve the sperm DNA integrity and reduce fragmentation. Testicular aspiration of sperm, followed by IVF or ICSI, may be recommended to avoid further damage that may be caused by ejaculation.

Understanding sperm health

While trying to have a baby, it is crucial to take a holistic approach to fertility care. Both partners need to have as much information as they can about their reproductive health to effectively plan for their aims. Taking tests like DNA fragmentation test and SpermQT, the individual can understand so much about his biology. This will help him make decisions and take charge of their path to achieving their goal, which is pregnancy.