Male infertility Flashcards
What do pathophysiological conditions impact?
Male fertility.
What is less widely recognised?
That male factors contribute to 50% of cases of infertility.
What is recommended?
A full medical history of the couple.
What is varicocele?
A varicose vein in the scrotum.
For what is the the counter current heat exchange necessary?
To help keep the testis cooler than body temperature.
Why does counter current heat exchange that help to keep the testis cooler than body temperature not work efficiently?
Because varicocele is essential for that.
What is nutrient and waste exchange equally?
Impaired.
Why is the nutrient and waste exchange impaired?
So the testis are likely to suffer greater stress.
What does greater stress affect?
Spermatogenesis.
In what does hypogonadotropic hypogonadism result?
In failed puberty.
Why does hypogonadotropic hypogonadism result in failed puberty?
Due to low testosterone.
What do elevated temperature and physical damage impair?
Spermatogenesis.
What do bacterial and viral infections cause?
Elevated stress .
Why do bacterial and viral infections cause elevated stress?
Due to direct damage.
What are some examples of bacterial and viral infections that cause elevated stress?
LPS from bacteria.
Reactive oxygen species stress.
Inflammation from the immune response.
What is Kalmann syndrome?
A well recognised genetic condition.
About what is there an increasing awareness?
About the contribution of genetic defects.
What do genetic defects affect?
Spermatogenesis.
Sperm specific proteins.
What can drugs and alcohol lower?
Testosterone levels.
What factor do anabolic steroids mimic?
Testosterone.
What do anabolic steroids cause?
Negative feedback into the hypothalamus and pituitary.
What do anabolic steroids switch off?
Natural production of GnRH and gonadotropins.
What does chemotherapy target?
Rapidly dividing cells.
What happens to spermatogonia when chemotherapy targets dividing cells?
They are damaged.
What can occur as a consequence in male infertility?
Observable/measurable defects.
What is Azoospermia?
A deficit/loss of sperm production.
How is sperm morphology characterised as an assessment on sperm features?
Very subjective.
What is Globozoospermia?
The production of sperm with abnormal heads and no acrosome.
What can sperm with Globozoospermia not do?
Fertilise.
What is Asthenozoospermia?
Sperm with poor motility.
How many cases of male infertility have no obvious cause?
Up to 30%.
How much should semen volume be for examination of semen range?
Above 1.5ml.
With a pH of 7.2.
What should be investigated if volume is low?
Congenital bilateral absence of the vas deferens.
How much should sperm concentration be?
At least 15ml.
How much of sperm showing progressive forward motility should be?
Above 32%.
How much should total motility be?
Above 40%.
What do observed morphological abnormalities impact?
Fertility.
How many men with complete absence of normal form can achieve pregnancy naturally?
Approximately one third.
What does embroscope do?
Takes image of developing embryos in culture.
Uses an algorithm to predict which ones are developing normally.
For how long has computer assisted sperm analysis existed?
For a long time.
What does the algorithm track?
The sperm movement.
What does the algorithm give?
Various readings on the pattern.
Speed of sperm movement.
What are the main parameters in the reading pattern of sperm movement?
Straight line velocity.
Average path velocity.
Curvilinear velocity.
Amplitude of lateral head displacement.
In what can the parameters of sperm movement reading be useful?
In diagnosing asthenozoospermia.
To where do the molecular defects contribute?
To the hitherto unknown causes of male infertility.
What are 2 prominent examples of causes of male infertility?
Mutations in the sperm ion channel CatSper.
Loss of PLC-zeta.
Where can loss of acrosome function be measured?
In the laboratory.
What does the western blot show?
A complete lack of PLC-zeta in globozoospermia cases.
One failed fertilisation case.
What do further studies support?
Loss of PLC-zeta as a cause of total failed fertilisation at IVF.
What do infertile men have?
More sperm with very low or failed acrosome reaction rates.
What are the three assisted reproductive technology treatment pathways?
IUI.
IVF.
ICSI.
With what does the success of all treatment pathways decrease?
With age of the woman who is using her own eggs.
By what do the key events encounter?
By sperm as they travel from the testes to the egg.
What is the association between ART procedure and the length of the dashed lines?
The more complex the ART procedure the greater the length of the dashed lines.
What does IUI mean?
Intrauterine insemination.
What do the mutations in genes cause?
Production of CatSper.
What is CatSper?
A very complex channel.
Of what does CatSper consist?
At least 10 subunits.
What mutations in genes are found in humans?
Mutations in genes for subunits 1 2 and epsilon.
With what is a microdeletion in exon 18 of the CatSper auxiliary subunit epsilon gene associated?
With loss of CatSper function in sperm.
In what does loss of CatSper function in sperm result?
In infertility.
In what does homozygous 6-base pair in frame deletion in exon 18 of CATSPER EPSILON result?
In a loss of Methionine799 and Alanine800 in the putative extracellular domain of CATSPER EPSILON protein.
In what does the loss of Methionine799 and Alanine800 in the CATSPER EPSILON protein result?
In production of ICatSper-null sperm.
What do ICatSper-nullsperm not have?
Overt signs of sperm dysfunction.
Tow hat does P4 fail?
To elicit an increase in calcium concentration in cell populations.
How is male infertility diagnosis beyond hormonal and crude semen assessment characterised?
Limited.
Thanks to what are novel causes slowly being reported?
To combined phenotypic and genetic analysis.
What is the challenge of male infertility?
To find new methods of treating the male that doesn’t involve also treating the female.
