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Male Factor InfertilityAll men should have a semen analysis performed during the initial infertility evaluation. It is frustrating to see couples that have done empiric therapy with Clomid later to find that a male factor is present that lowers the efficacy of this drug. A male factor may be the only factor in about 20 % of couples and is a contributory factor in about 40 % of patients. When a male factor is present the count, motility, and morphology (sperm shape) are abnormal in most cases but not always. The
normal semen parameters are below:
Many couples wonder if the ‘abnormal’ sperm will produce ‘abnormal’ children. Abnormal sperm (i.e. two heads, two tails, etc.) probably are unable to fertilize eggs. By the criteria above even a normal semen analysis will have some ‘abnormal’ sperm. The initial infertility consultation will cover important aspects of the male medical history. Medical illnesses such as diabetes or hypertension may affect sperm counts. Surgeries such as varicocele repair, hernia repair, and vasectomy reversal are important. Environmental toxins and smoking may lower the sperm concentration. Medications such as herbals (i.e. St. John’s Wort, echenacia, and others), antihypertensives, anabolic steroids, or androgens may affect sperm. Some men are treated with decreased libido are given Testosterone therapy. This hormone therapy will suppress the pituitary production of FSH and LH and therefore lead to decreased sperm production by the testes. Given the fact that it takes about 80 days for a mature sperm to be produced, the effect of this therapy may be profound in terms of time to recover. The physical examination will make note of body habitus, hair distribution, secondary sexual characteristics, presence or absence of the vas deferens, and testicular size. Generally, after an abnormal semen analysis is found two times we refer the male to a urologist specifically trained win infertility. Tests of sperm function
Important Causes of Male Factor InfertilityAzoospermia The complete lack of sperm is called azoospermia.
This can be due to either a lack of production, lack of transport, or a
lack of appropriate hormonal stimulation of the testes. Men with obstructive azoospermia commonly have mutations in the gene for cystic fibrosis (CF). CF is the most common fatal autosomal recessive condition in the Caucasian population with 1/25 carrier frequency. CF is found in 1/2500 live births. Gene testing will identify about 70% of patients with CF. In most with CF, the epididymis does not develop resulting in congenital absence of the vas deferens (CAVD). 50% to 80% of men with CAVD without pulmonary or digestive problems have a mutation . Given the high incidence of mutations, the female partner should be tested. She has a 1:25 chance
to be a carrier. Some small studies found mutations in CF with
unexplained infertility and non-obstructive azoospermia. Interestingly,
if a man had CAVD and renal anomalies, no CF mutations are found. Thus
we should evaluate the kidneys. Varicocele The testis functions normally at a temperature normally a few degrees less than body temperature. If the veins surrounding the testes dilate the temperature may be elevated. This may lead to abnormal shape, concentration, or motility. The condition may be detected by physical exam or ultrasound exam. Options for treatment include surgery, intra-uterine insemination, expectant management, or IVF with ICSI depending upon the specific situation. New Concept: Genetic risks of ICSI - Intra-cytoplasmic sperm injection with IVFFrom the above it is clear that our understanding of male infertility
is advancing rapidly. Several large studies have shown that minor and major malformations were the same with ICSO patients compared to the normal population, about 3%. However, one type of genetic anomaly does appear to be increased; sex-chromosome aneuploidy (abnormal numbers of the sex chromosomes, Y and X). The normal rate is about 0.2 % but with ICSI patients it is about 0.8%. That is 8 abnormal chromosome patients out of 997 total patients. It is important to discuss the genetic implications of ICSI. We should consider karyotype testing, Y chromosome micro-deletion testing, and partner CF mutation testing prior to IVF-ICSI. Indications for ICSI generally include male factor
infertility and prior failed fertilization in IVF. It is debatable if we
should do ICSI for unexplained infertility in the presence of normal
sperm. The ICSI needle has the potential to damage the spindle apparatus
which is the fine filaments that shuttle the dividing chromosomes to
either side of the dividing cell. The potential exists for the
separation of chromosomes to be abnormal.
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