MALE INFERTILITY

MALE INFERTILITY

INTRODUCTION : 

  • Infertility incidence
  • Male Factor Rising up off of the Population

Male Infertility

  • Responsible for 1/3rd of IVF treatments
  • Off of the cases idiopathic or unexplained
  • Mainstay of treatment ART ( IVF/ICSI )
  • Live birth after ICSI – 25-30% PER (fresh ) treatment cycle 

CAUSES :  

Lifestyle Factors and Male Infertility : 

Obesity and Weight Loss :

  • Statistically Significant relationship between obesity & semen analysis parameters
  • Obese men more likely to be oligospermic or azoospermic
  • Paternal obesity negatively affects ART outcome
  • Conflicting results regarding effect of significant weight loss on semen analysis parameters

Diet :  

  • Vegetables , fruits , fish , poultry , cereals & low-fat dairy products – positively associated with sperm quality
  • Processed meat , full-fat dairy products , alcohol , coffee & sugar-sweetened beverages – poor semen quality & lower fecundity rates
  • Favourable effects of selenium , zinc , omega-3 fatty acids , coenzyme Q10 & Carnitines on Semen Parameters

Vitamins and Antioxidants :

  • Oxidative Stress (OS) can impair sperm motility, reduce fertilizing ability & cause sperm DNA damage
  • Antioxidants can protect cells from OS
  • Many antioxidant supplements commercially available , but none has high-quality clinical data
  • Antioxidant use : increase live birth rate (OR 1.79) increase clinical pregnancy rate (OR 2.9 )
  • Overall low quality evidence

Cigarette Smoking and vaping : 

  • Smoking negatively affects semen quality but underlying mechanism not yet clear
  • No definite relationship between smoking & male infertility but current available evidence supports smoking cessation & decreasing tobacco exposure for couple trying to conceive
  • Smoking associated with decrease semen count , motility & abnormal morphology – leads to decrease in sperm quality in both fertile & infertile men ( higher effect in infertile )
  • Worsened semen quality in moderate & heavy smokers
  • Oligospermia more prevalent in smokers ( RR 1.29 )
  • Paternal smoking adversely affects ART outcomes
  • Risk of treatment failure (specially miscarriage ) reduces by 4 % in former smokers with each additional year following smoking cessation
  • Vaping refers to e-cigarettes which contain propylene glycol , vegetable glycerine , nicotine , food-grade flavouring & water . Generally viewedas less harmful but does have negative effect on spermatogenesis & OS

Alcohol :  

  • >50 % men drink alcohol yet effect on male fertility not understood
  • Overall –lower semen quality but variable & dose – dependent effect on semen parameters
  • Habitual alcohol intake – decrease semen quality & changes in reproductive hormones
  • Semen volume , sperm count , motility & number of morphological normal sperm ALL decreased significantly

Caffeine :

  • Apparently unaffected semen characteristics but male coffee drinking associated with prolonged time to pregnancy
  • May be associated with sperm aneuploidy & DNA breaks but no other DNA damage

Stress : 

  • Psychological stress – decrease sperm concentration , progressive motility & increase fraction of sperm with abnormal morphology
  • Primarily caused by suppression of testosterone by increase corticosteroid levels
  • Antidepressants drugs – Negatively affect sexual function & semen quality
  • Manage stress non – pharmacologically – CBT , Psychotherapy , fertility counselling & support   

Sleep :

  • Slepp duration associated with testis size in healthy young men
  • Sleep disturbance may contribute to male infertility
  • Testosterone has diurnal pattern & increase coinciding with REM Sleep ( rather than melatonin )
  • Prolactin increase during sleep & levels are sleep – dependent
  • Co-effects if stress / depression & poor sleep on fertility
  • Long –term use of hypnotics – not recommended

Sperm assessment and selection

Semen Analysis ( SA ) 

  • Essential in evaluation & initial lab test
  • Single SA usually sufficient to decide the most appropriate management pathway
  • If initial SA ≥ 1 abnormal parameters – consider Repeat
  • Men with risk factors or abnormal semen parameters – refer to male reproductive specialist for full evaluation

Sperm DNA Fragmentation 

  • SA has limited diagnostics accuracy & cannot predict ART outcomes
  • Association between high Sperm DNA Fragmentation & poor reproductive outcomes in natural conception / IUI but unable to predict with ART outcomes
  • No treatment for high Sperm DNA Fragmentation proven yet 

New developments in sperm selection in ART :

  • Sperm selection –Standard methods are density gradient centrifugation or swim-up both with similar ART outcomes
  • Live births after ICSI – 25-30% per ( fresh )treatment cycle

Genetic testing in male infertility :  

  • Genetic Testing and karyotyping– in klinfelter Syndrome ( 47,XXY), testicular disorder of sex development ( 46 , XX ) , translocation ( balanced or unbalanced ), inversions, insertions or deletions