The cause of male factor infertility is often unknown. However, some causes have been identified, including problems related to:
• sperm production
• the anatomy or structure of the man's reproductive organs
• the man's immune system
Sperm Production Disorders
Male factor infertility may occur if sperm are produced in low numbers, or if many of the sperm produced are abnormal in shape or not able to move well. Abnormally shaped sperm may not be able to penetrate and fertilize an egg. Sperm that do not move well may not reach the egg. Some causes of sperm production disorders may include a genetic defect, infection, testicular trauma, hormonal imbalance or exposure to radiation and certain medications.
Anatomical or Structural Problems
Anything that blocks the pathways in which the sperm travel may cause infertility. Structural problems may be caused by scar tissue that formed as a result of a previous surgery or from an infection in the pathways. Varicose veins that develop in the testes may also interfere with sperm production. Some structural defects may be congenital (from birth).
Immune System Disorders
Some men develop antibodies to their own sperm, which may attack and weaken the sperm. Also, the antibodies may attach to the sperm and interfere with their movement or their ability to fertilize the egg.
At Androcare, We offer specialized tests and services for the evaluation of male infertility which include:
Sperm Chromatin Structure Assay (SCSA)
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. Results reported in the scientific literature have shown that regardless of the assisted reproductive technology used, an elevated level of DNA fragmentation above the critical threshold will significantly compromise the possibility of a successful pregnancy.
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
DNA fragmentation levels are closely correlated with IUI, IVF and ICSI miscarriage and pregnancy rates
DNA fragmentation is significantly higher in subfertile men.
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
Advantages of the Sperm DNA Fragmentation test
This test provides a reliable analysis of sperm DNA integrity that may help to identify men who are at risk of failing to initiate a healthy ongoing pregnancy. Information about sperm DNA integrity may help in the clinical diagnosis, management and treatment of male infertility and may be of prognostic value in assessing outcome of assisted conception treatment.
High Rates of Sperm DNA Fragmentation and Pregnancy
Normal, healthy pregnancies do occur in couples where the male partner has a high percentage of sperm with fragmented DNA, although the chances are significantly reduced, as the percentage of sperm bearing low levels of DNA fragmentation is much lower. 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, so a couple coming for assisted conception treatment where the sperm DNA fragmentation level is high has a better prognosis if his partner is young.
Causes of Sperm DNA Fragmentation
A major causative factor for sperm DNA damage is oxidative stress. Other factors include abnormalities in the regulation of apoptosis, or defects in topoisomerase activity. Increased sperm DNA fragmentation is associated with:
sperm cytoplasmic droplets
elevated testicular temperature
exposure to environmental and occupational pollutants
Indications for Male Patients who may benefit from the Test
arrested embryo development
poor blastocyst development
multiple failed IVF/ICSI treatment
recurrent miscarriage in partner
poor semen parameters
exposure to harmful substances
Some causes of DNA fragmentation cannot be treated, but if the damage is caused by free radicals, then a change in lifestyle and a diet designed to protect against oxidative stress may help reduce the levels of DNA fragmentation in some of these cases. Treatment of infection with antibiotics would also be expected to reduce DNA fragmentation. There is some evidence to show that varicocoele repair may improve sperm DNA integrity. Initiatives to reduce the levels of fragmentation can be assessed by undertaking a second test three months after the first. 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.
What is the DNA fragmentation test?
This test is an effective method for measuring thousands of sperm in an ejaculate. Sperm are stained with a fluorescent probe that interacts with the DNA molecule. The fluorescence signal changes when the DNA is fragmented, and this is monitored using a flow cytometer. The SCSA® test has been developed over the last 20 years and is CLIA approved.
The results are reported showing 3 statistical categories of fertility potential :
DNA Fragmentation Index (%DFI; % sperm cells containing damaged DNA)
< 15% DFI = excellent fertility potential
> 15 to < 30% DFI = good fertility potential
> 30% DFI = fair to poor fertility potential*
The statistically significant DFI threshold for subfertility has been established at > 30%.
Normal full-term pregnancies are possible with an elevated DFI, but the higher the level of fragmentation, the greater the incidence of reduced term pregnancies and miscarriage.
High DNA stainability (HDS; % cells with immature chromatin)
< 15% HDS = normal
> 15% HDS = above normal
Immature chromatin can be measured by high DNA stainability (HDS) and is associated with asyngamy and poor IVF fertilisation rates when it exceeds 15%
Reactive Oxygen Specie Test (ROS)
The seminal plasma is well endowed with an array of antioxidants that act as free radical scavengers to protect the spermatozoa against oxidative stress. Sperm that have been exposed to oxidative stress have reduce motility, lower capacity to sperm-oocyte binding and fusion, and sperm DNA damage.
It is possible that excessive reactive oxygen species (ROS) generation by the human spermatozoa contributes to the aetiology of the male infertility. The result of such an oxidative stress is the induction of lipid per oxidation in the sperm plasma membrane, suppression of the sperm functions, and the precipitation of the DNA damage to both the nuclear and the mitochondrial genomes.
Androcare Laboratories can perform an assay that is reliable and sensitive to measure a possible excess of superoxide anions present in the ejaculate.
Hyaluronan Binding Assay
The Sperm Hyaluronan Binding Assay is a qualitative assay for the maturity of sperm in a fresh semen sample. This additional information will help the attending physician to identify patients with poor reproductive prognosis in Intra-Uterine Insemination (IUI) and In- vitro Fertilization (IVF). It is not intended to be a single diagnostic indicator of potential fertility.
Sperm after washing and removal of seminal plasma are cultured for extended period of time. The motility of spermatozoa is then checked after 24 hours. The specimen is considered normal if more than 70% of the sperms are alive and moving at 24 hours.
Retrograde Semen Analysis
A Retrograde Semen Analysis is indicated for patients with a low volume and a diminished sperm count in the initial semen analysis. Retrograde ejaculation is the ejaculation of sperm into the bladder. Urine released following sexual activity will contain sperm in men who undergo retrograde ejaculation.
Many retrograde ejaculation patients will have had prior surgery or a medical condition that predisposes them to retrograde ejaculation, such as testicular cancer surgery (RPLND), transurethral surgery of the prostate, or childhood bladder surgery etc. Medical conditions such as diabetes, MS, or spinal cord injury may also predispose an individual to retrograde ejaculation.
The morphology of the sperm may be predictive of a patient’s fertility potential even in cases where the overall parameters of the semen analysis are normal. The Strict Morphology assay takes a critical look at the individual spermatozoa according to a strict set of criteria. The sperm are stained and then examined under oil immersion at 1000X power for proper size and shape of the head, midpiece, tail, or for any abnormalities. A single or multiply defect in any parameter rates the spermatozoa as abnormal. A relatively low number of sperm are rated as “normal” or essentially near-perfect during a typical Strict Morphology test, as compared to the estimated morphology done during a Complete Semen Analysis. The result is an assay that can distinguish very fine differences in morphology from one specimen to the next, and yields a quantifiable result that is indicative and predictive of the entire sperm population’s potential fertility function. Semen specimens that are treated or processed with selective gradient media generally show an improved strict morphology result. A Complete Semen Analysis should be ordered along with this assay.
The presence of anti-sperm antibodies is associated with immunological fertility impairment. Semen specimens with anti-sperm antibodies (ASA) can often present themselves with motile sperm caught in clumps together (agglutinated). While there are several classes of ASA, only those of the IgG and IgA classes are clinically significant. IgA antibodies rarely if ever occur without IgG antibodies also being present. Therefore, testing for IgG is sufficient for routine screening of semen samples for anti-sperm antibodies. The ASA assay uses the direct method of testing by mixing fresh, untreated semen with latex particles that have been coated with human IgG. To this mixture is added a monospecific antihuman IgG antiserum. The formation of agglutinates between the particles and motile sperm indicates the presence of IgG antibodies on the sperm. A Complete Semen Analysis should be ordered along with the assay.
Post Vasectomy Semen Analysis
Patients who have had a vasectomy should be checked for the presence of sperm in the ejaculate as part of their routine follow-up starting two weeks post surgery to verify the success of the procedure. A patient’s semen is considered free and clear of sperm when they have two consecutive Post Vasectomy Semen Analysis (PVSA) that show no sperm, motile or non-motile, on the direct exam or centrifuged pellet. A follow up analysis is also encouraged at six months post-surgery to rule out the possibility of a spontaneous reconnection. The principle function of the PVSA is to check for the presence or absence of sperm.