Male Factor Infertility Flashcards
What is the role of semen analysis?
Semen analysis is used to examine the quantity and quality of semen and sperm. It assesses for male factor infertility.
How is a sample of semen provided?
Men should be given clear instructions for providing a sample:
- Abstain from ejaculation for at least 3 days and at most 7 days
- Avoid hot baths, sauna and tight underwear during the lead up to providing a sample
- Attempt to catch the full sample
- Deliver the sample to the lab within 1 hour of ejaculation
- Keep the sample warm (e.g. in underwear) before delivery
What factors may affect the quality of a semen sample?
Several lifestyle factors may affect the results of semen analysis and the quality and quantity of sperm:
- Hot baths
- Tight underwear
- Smoking
- Alcohol
- Raised BMI
- Caffeine
When is a repeat sample required?
A repeat sample is indicated after 3 months in borderline results or earlier (2 – 4 weeks) with very abnormal results.
What are the normal parameters of semen and sperm?
Note: semen volume, semen pH, concentration of sperm, total number of sperm, mobility of sperm, vitality of sperm and percentage of normal sperm
Normal results indicated by the World Health Organisation are:
- Semen volume (more than 1.5ml)
- Semen pH (greater than 7.2)
- Concentration of sperm (more than 15 million per ml)
- Total number of sperm (more than 39 million per sample)
- Motility of sperm (more than 40% of sperm are mobile)
- Vitality of sperm (more than 58% of sperm are active)
- Percentage of normal sperm (more than 4%)
What is polyspermia?
Polyspermia (or polyzoospermia) refers to a high number of sperm in the semen sample (more than 250 million per ml).
What is normospermia?
Normospermia (or normozoospermia) refers to normal characteristics of the sperm in the semen sample.
What is oligospermia?
Oligospermia (or oligozoospermia) is a reduced number of sperm in the semen sample. It is classified as:
- Mild oligospermia (10 to 15 million / ml)
- Moderate oligospermia (5 to 10 million / ml)
- Severe oligospermia (less than 5 million / ml)
What is cryptozoospermia?
Cryptozoospermia refers to very few sperm in the semen sample (less than 1 million / ml).
What is azoospermia?
Azoospermia is the absence of sperm in the semen.
Briefly describe the pre-testicular causes of male infertility
Testosterone is necessary for sperm creation. The hypothalamo-pituitary-gonadal axis controls testosterone. Hypogonadotrophic hypogonadism (low LH and FSH resulting in low testosterone), can be due to:
- Pathology of the pituitary gland or hypothalamus
- Suppression due to stress, chronic conditions or hyperprolactinaemia
- Kallman syndrome
Briefly describe the testicular causes of male infertility
Testicular damage from:
- Mumps
- Undescended testes
- Trauma
- Radiotherapy
- Chemotherapy
- Cancer
Briefly describe the genetic or congenital causes of male infertility
Genetic or congenital disorders that result in defective or absent sperm production, such as:
- Klinefelter syndrome
- Y chromosome deletions
- Sertoli cell-only syndrome
- Anorchia (absent testes)
Briefly describe the post-testicular causes of male infertility
Obstruction preventing sperm being ejaculated can be caused by:
- Damage to the testicle or vas deferens from trauma, surgery or cancer
- Ejaculatory duct obstruction
- Retrograde ejaculation
- Scarring from epididymitis, for example, caused by chlamydia
- Absence of the vas deferens (may be associated with cystic fibrosis)
- Young’s syndrome (obstructive azoospermia, bronchiectasis and rhinosinusitis)
What is the initial investigations for male inferility?
The initial steps for investigating abnormal semen analysis include a history, examination, repeat sample and ultrasound of the testes.
