Causes of Male Factor Infertility

There are several causes of male factor infertility: genetic, hormonal, varicocele, infection, anatomical malformations, chemical insult, idiopathic oligospermia accounts for 30%. Below we are going to explore several factors:

Genetic Factors

• Chromosomal abnormality can be found in about 15% of azoospermic men and 6% of
  men with severe oligospermia.
• Klinefelter syndrome (47XXY)
  – Nondisjunction in meiosis 1 or 2
• Congenital absence of the vas deferens
• Kallman’s syndrome-genetic condition that results in hypogonadotropic hypogonadism
  (and inability to smell)

Y Chromosome Microdeletion

• Missing gene(s) in the long arm of the Y chromosome that are associated with
  spermatogenesis
• May not have any symptoms but reduced fertility
• Prevalence about 7%

Factors Affecting Spermatogenesis

• Stress
• Age
• Toxins (lead, plastics, tobacco, ETOH, cannabis)
• Exposure to radiation or chemo
• Prolactinoma
• Cryptorchidism (absence of one or both testes from the scrotum) usually undescended and will descend by first year of life.
• Infections:
  – Mumps, chickenpox, STDs
  – Can cause orchitis (testicle infection)
  – Prostatitis
• Heat- hot tubs, sauna, long distance running, biking, truck drivers, tight underwear

Varicocele

• 35% of subfertile men
• Lower sperm count and quality
• Lower sperm function
• Elevated oxidative stress-elevated sperm DNA damage

*Miyaoka & Esteves, Adv Urol 2012; Agarwal, Esteves, Hamada; Nature Urol Rev 2013

Varicocele Repair

• Varicocelectomy
  – Done under microscopic guidance might improve outcome
  – Wait around 6 months to resume treatment
  – 60-70% show improvement
  – 40-50% pregnancy rate

ASRM Practice Guideline- Varicocele Tx

• Indications for varicocele repair
  – Infertile couples
  – Normal female or treatable female infertility
  – Abnormal S/A or sperm function test
• Some studies have shown that treating the varicocele prior to ICSI can increase # of fertile eggs, live birth % and miscarriage rate (Esteves, SC et al, journal of urology vol 184: 1442-6, 2010)
• Probability of semen improvement: 50-70%

Male Obesity

• Increases risk of hypogonadotropic/hypogonadism (leptin alters GnRH)
• Is risk factor for subfertility
• Negative correlation between elevated BMI, Total and Free T
• Oligo- and Asthenospermia increase with increasing BMI
• Decreases sperm, embryo quality and placental development
• In animal study, rate of embryo implantation and fetal development decreased in mice with obese fathers by up to 15%*.

*Binder, et al. 2012. Abstract presented at ESA-SRB