Male Factor Infertility Flashcards
What is the purpose of semen analysis?
- it assesses semen / sperm quantity and quality
- it can identify male factor infertility
What instructions should be given to men prior to providing a sample?
- abstain from ejaculation for at least 3 days and at most 7 days
- avoid hot baths / sauna / tight underwear in the lead up
- attempt to catch the full sample
- deliver the sample to the lab within 1 hour of production
- keep the sample warm before delivery (e.g. in underwear)
What lifestyle factors can affect the quality / quantity of sperm?
- hot baths
- tight underwear
- smoking
- alcohol
- raised BMI
- caffeine
When should a sample be repeated if results are borderline / abnormal?
- repeat sample after 3 months if results are borderline
- repeat sample within 2-4 weeks if results are very abnormal
What is a normal semen volume and pH?
- volume > 1.5ml
- pH > 7.2
What is a normal sperm concentration and total number per sample?
- normal concentration is > 15 millon per ml
- total number should be > 39 million per sample
What is normal motility and vitality of sperm?
- more than 40% of sperm should be mobile
- more than 58% of sperm should be active
What should the percentage of normal sperm in a sample be?
there should be > 4% normal sperm in a sample
What is polyspermia?
(also called polyzoospermia)
- a high number of sperm in the semen sample
- this is > 250 million per ml
What is normospermia?
also called normozoospermia
the sperm in the semen sample have normal characteristics
What is oligospermia?
(also called oligozoospermia)
- there is a reduced number of sperm in the semen sample
- mild oligospermia when 10 - 15 million per ml
- moderate oligospermia when 5 - 10 million per ml
- severe oligospermia when < 5 million per ml
What is cryptozoospermia?
- there is a very low number of sperm in the semen sample
- this is < 1 million per ml
What is azoospermia?
the absence of sperm in the semen sample
What is the underlying mechanism causing pre-testicular male infertility?
- testosterone is necessary for sperm creation
- testosterone is controlled by the hypothalamo-pituitary-gonadal axis
- hypogonadotrophic hypogonadism means that there are low FSH / LH levels, resulting in low testosterone
What can cause hypogonadotrophic hypogonadism?
- pathology of the pituitary gland or hypothalamus
- suppression due to stress, chronic conditions or hyperprolactinaemia
- Kallman syndrome
What is Kallman syndrome?
- a rare disease characterised by a lack of GnRH
- it is characterised by hypogonadotropic hypogonadism and an impaired sense of smell
- it is diagnosed at puberty due to lack of sexual development
What factors causing testicular damage can result in infertility?
- mumps
- undescended testes
- trauma
- radiotherapy
- chemotherapy
- cancer
What congenital / genetic conditions can result in defective / absent sperm production?
- Klinefelter syndrome
- Y chromosome deletions
- Sertoli cell-only syndrome
- anorchia (absent testes)
Klinefelter = males possessing one or more additional X chromosomes
What is meant by a post-testicular cause of infertility?
an obstruction that prevents sperm from being ejaculated
What are the possible post-testicular causes of male factor infertility?
- damage to the testicle / vas deferens from trauma, surgery or cancer
- retrograde ejaculation
- ejaculatory duct obstruction
- scarring from epididymitis (e.g. from chlamydia)
- absence of the vas deferens (seen in cystic fibrosis)
- Young’s syndrome
What is Young’s syndrome?
characterised by a triad of:
- azoospermia
- bronchiectasis (damaged airways in the lungs + thick, sticky mucus production)
- rhinosinusitis
also known as sinusitis-infertility syndrome
What are the initial steps for investigating abnormal semen analysis?
- history
- examination
- repeat sample
- USS of the testes
What further investigations may be considered in patients with abnormal semen results?
- hormone analysis - FSH, LH + testosterone
- genetic testing
- further imaging (MRI / transrectal USS)
- vasography
- testicular biopsy
What is a vasography?
- contrast is injected into the vas deferens
- XR images are taken to assess for any obstruction
What are the options for management of male factor infertility?
- surgical sperm retrieval (in obstruction)
- surgical correction of obstruction in the vas deferens
- intra-uterine insemination
- ICSI
- donor insemination
