.svg)
E-Brochures
The genetic integrity of the spermatozoan is essential for normal embryo development. A high level of DNA fragmentation in sperm cells may represent a cause of male infertility that conventional examinations - sperm concentration, motility analysis, morphology assessment - cannot detect.
High sperm DNA fragmentation does not appear to affect fertilisation or the first or second embryo cleavage stages
High sperm DNA fragmentation can affect embryo cleavage once the paternal genome is switched on, and subsequent blastocyst development
Men with poor semen parameters are more likely to have high DNA fragmentation
High sperm DNA fragmentation is also found in men with normal semen parameters
High Rates of Sperm DNA Fragmentation and Pregnancy
Embryos derived from sperm whose DNA is highly fragmented have a poor prognosis. Evidence suggests that this could result in initiation of apoptosis and mutations resulting in blastocyst arrest, miscarriage, abnormalities in the offspring and an increased susceptibility to childhood cancer. Protection against high DNA fragmentation may be afforded by younger oocytes which are much more efficient at DNA repair of defective sperm than older oocytes.
Causes of Sperm DNA Fragmentation
Abnormalities in apoptosis regulation
Defective topoisomerase
Infection
Leucocytospermia
Sperm cytoplasmic droplets
Febrile illness
Elevated testicular temperature
Diet
Drug use
Cigarette smoking
Environmental pollutants
Advanced age
Varicocoele
A dry orgasm
Unexplained infertility
Arrested embryo development
Poor blastocyst development
Multiple failed IVF/ICSI treatment
Recurrent miscarriage in partner
Advanced age
Varicocoele
Poor semen parameters
Exposure to harmful substances
Initial reports suggest that DNA damage occurs at the post-testicular level, so that testicular sperm may have a healthier DNA integrity than ejaculated sperm. Furthermore, studies show that ICSI may be a more effective treatment than IVF for sperm with a high DNA fragmentation.
When % DFI is above 25 %, current literature suggests that the patient either try to reduce the DFI by medical intervention or change of lifestyle, or skipping IUI and go on to IVF ICSI for greatest success
Hypothesis: A high ratio of moderate DFI to high DFI sperm may be the most negative since moderate DFI sperm have normal nuclear morphology and will likely fertilise but may have DNA damage beyond the repair capacity of eggs.
High DNA stainability (HDS): % sperm with immature chromatin and abnormal proteins. Levels in the > 25% range are considered negative for pregnancy outcome