Investigations of Infertility Flashcards
What investigations are used to assess for male infertility?
- Semen analysis
- Analysis of sperm DNA
- Endocrine assessment
- Cytogenic studies
- Testicular/epididymal biopsy
- Tests for retrograde ejaculation
- Immunological tests
What is the most useful investigation into male infertility?
Semen analysis
How are semen samples collected?
Masturbation into a sterile container after 3 days abstinence and examined within 2 hours of collection
Where is the best place for semen sample collection?
In a private room adjacent to the androgeny laboratory to avoid cooling during transportation
What is the lower limit of normal semen volume?
1.5ml
What is the lower limit of normal total sperm number?
39x10^6 per ejaculate
What is the lower limit of normal sperm concentration?
15x10^6 per ml
What is the lower limit of normal total sperm motility?
40%
What is the lower limit of normal progressive sperm motility?
32%
What is the lower limit of normal sperm vitality (live sperm)?
58%
What is the lower limit of normal sperm morphology?
4%
What are the main features looked at in seme analysis?
- Volume
- Sperm concentration
- Motility
What is the semen volume range for 80% of fertile males?
1-4ml
What may a low semen volume suggest?
Androgen deficiency
What may a high semen volume suggest?
Abnormal accessory gland function
What is absence of sperm in semen called?
Azoospermia
What does azoospermia indicate?
Sterility
How may sperm be obtainable in azoospermia?
- Percutaneous epididymal aspiration
- Testicular aspiration
- Testicular biopsy
Why should findings if sperm concentration not be accepted on a single sample?
Can vary from day to day
What might abnormally high values of sperm concentration be associated with?
Subfertility
What would be an abnormally high sperm concentration?
> 200 million per ml
What % of sperm should show good motility within an hour of collection?
60%
How does WHO grade sperm motility?
Grades 1-4
What is grade 1 sperm motility?
Rapid and linear progressive motility
What is grade 2 sperm motility?
Slow or sluggish linear or non-linear motility
What is grade 3 sperm motility?
Non-progressive motility
What is grade 4 sperm motility?
Immotile
Why may analysis of sperm DNA be performed as an investigation for infertility?
Integrity of sperm DNA is essential for normal fertilisation and transmission of paternal genetic information
What may damage to sperm DNA lead to?
Impaired fertility
What endocrine results suggest testicular damage?
High serum concentrations of FSH and low AMH
What endocrine results suggest male hypopituitarism?
Low or undetectable FSH and LH
What endocrine results are found in spermatogenic failure?
High FSH, low AMH and azoospermia
What may hyperprolactinaemia cause in males in terms of infertility?
Impotence or oligospermia
What should be looked for on cytogenic tests for male infertility?
XXY or XYY karyotypes
What genetic condition should oligospermic men be screened for?
Cystic fibrosis
Why is it important to screen oligospermic men for CF?
They may be healthy carriers and conceive with assistance to produce a child with CF if their partner is a carrier
Why can a testicular/epididymal biopsy be useful in assessing male infertility?
- May demonstrate spermatogenesis even if elevated concentrations of gonadotrophins
- Sperm can be aspirated and cryopreserved for later
How can retrograde ejaculation be investigated?
Detecting spermatozoa in the urine
When should retrograde ejaculation be considered as a more likely cause of infertility?
Following TURP
Why are immunological tests a useful investigation for infertility?
Autoimmunity to sperm can cause infertility
What class are the anti-sperm antibodies?
IgG and IgA
What is the first step in assessing female infertility?
Examination
What are the important aspects of an examination for female infertility?
- Signs of hirsutism
- Abdominal examination
- Gynaecological examination
- Bimanual examination
What are some associated features of hirsutism?
- Facial hair
- Acne
- Male pattern alopecia
- Pubic hairline extending to umbilicus
What findings on bimanual examination might explain infertility?
- Adnexal mass from ovary or tubes
- Tenderness suggesting PID or endometriosis
- Presence of uterine fibroids
What is the first step in assessing ovulation?
Detecting if it is taking place
If a regular menstrual cycle is present what measures can be used to investigate whether ovulation is taking place?
- Changes in basal body temperature or cervical mucus
- Measurement of hormonal levels
- Endometrial biopsy
- Ultrasound
Are measurements of body temperature and cervical mucus recommended as indicators of ovulation?
No
Why is measuring body temperature not recommended as a way of identifying ovulation?
Difficult and increases the stress with a daily reminder of failure to conceive
Why is monitoring cervical mucus not recommended as a way to identify ovulation?
Many women find the assessment difficult
What changes in hormones suggests ovulation is taking place?
LH surge in blood or urine
When does the peak of the LH surge occur?
24 hours before ovulation
How can women assess their ovulation using hormones?
Commercially available LH detection kits
How can formation of the corpus luteum be demonstrated with hormone measurements?
Serum progesterone in the luteal phase
What progesterone measurement in the mid-luteal phase is suggestive of ovulation?
> 25mmol/L
How can ultrasound help assess ovulation?
- Transvaginal can be used to track follicle growth
- May help diagnosis of PCOS or ovarian endometrioma
How should evidence of anovulation be further investigated?
- Serum prolactin and TFT
- Serum FSH, LH and oestradiol on days 2 and 3 of natural or induced menstruation
- Measurement of AMH
If prolactinaemia is present in anovulation what additional test should be performed?
MRI or CT of sella turcica
How can ovarian reserve be assessed?
Using measurements of AMH in serum or antral follicle count with transvaginal ultrasound
What does a low age-related AMH or AFC predict?
Poor oocyte yield at IVF and lower chance of pregnancy
What does a higher AMH or AFC predict in infertility?
Better ovarian response to gonadotrophin stimulation
What is the limitation of assessing ovarian reserve?
Can predict oocyte quantity but not quality
What tests can be used to assess tubal patency?
- Hysterosalpingography
- Laparoscopy and dye insufflation
When is assessment of tubal patency necessary?
Before beginning ovulation therapy or intrauterine insemination
When is assessment of tubal patency not necessary?
If the couple are going straight to IVF
How is hysterosalpingography performed?
Radio-opaque dye injected into the uterine cavity and fallopian tubes to outline the uterus and tubes
How can hysterosalpingography show tubal patency?
Will highlight any obstructions and their site
When should hysterosaplingography be performed?
Within the first 10 days of the cycle
Why should hysterosalpingography be performed in the first 10 days of the cycle?
To avoid inadvertent irradiation of a newly fertilised embryo
What should women be screened for before hysterosalpingography?
Chlamydia trachomatis
Why should women be screened for chlamydia before hysterosalpingography?
Reduce the risk of reactivation of infection leading to pelvic abscess formation
What does laparoscopy help to identify when investigating infertility?
Directly visualises the pelvic organs to assess for endometriosis or adhesions
What is dye insufflation?
Methylene blue dye is injected through the cervix to test tubal patency
What is the ‘see and treat’ policy of diagnostic laparoscopy for infertility?
Allowing for rapid surgical treatment of minor degrees of endometriosis or adhesions
When is intervention for a pathology diagnosed on laparoscopy best left to another surgery?
When intervention may damage other pelvic structures to get full informed consent
What are the risks of laparoscopy?
- GA
- Damage to other pelvic structures
Why is laparoscopy preferred as a later investigation for infertility?
Due to its risks less invasive procedures are preferred first
When may a laparoscopy be the first line investigation for infertility?
Specific indications e.g. history of PID or appendicitis with peritonitis