Infertility Flashcards
List some factors that are increasing the demand for assisted conception therapy (ACT)
Increasing parental age
Increasing chlamydia
Male factor infertility
Improved success rates of ACT
List the main indications for ACT
Male factors Unexplained infertility Endometriosis Tubal disease Ovulatory disorder Single parents/same sex couples
At what age does fertility start to decrease?
27
Significantly so at 37
What should females limit their alcohol limit to per week to improve fertility?
4 units a week
What is the optimal weight for males + females to improve fertility?
BMI 19-29
What medical interventions should be assessed before ACT to improve fertility?
Folic acid
Check rubella immunity
Cervical smear
Blood-borne viruses screen
Which drug class in particular can cause male infertility/azoospermia?
Steroids (if abused)
How long should a female wait before trying to conceive after being vaccinated against rubella?
3 months
List all the assisted conception treatments available
Donor insemination Intra-uterine insemination (IUI) In vitro fertilisation (IVF) Intra-cytoplasmic sperm injection (ICSI) Surrogacy
What does intra-uterine insemination involve?
Sperm are injected into the uterine cavity around the time of ovulation
What does in vitro fertilisation involve?
Sperm and egg fertilise outside body and implanted into uterus
How is the normal menstrual cycle down-regulated in preparation for IVF?
Synthetic GnRH agonist administered as spray/injection
How is the ovary stimulated to cause follicular development?
Synthetic GH injection
What are the risks to GH injection?
Allergy
Ovarian hyperstimulation syndrome
How long must a male be abstinent before providing a sperm sample?
72 hours
What does intra-cytoplasmic sperm injection involve?
Injecting sperm into egg outside the body (i.e. no fertilisation)
What determines our gender?
Chromosomes (XY or XX)
Sex hormones secreted
External + internal genitalia
Psychological factor
Which chromosome has the sex-defining region?
Y-chromosome
Which 2 hormones/factors contribute to the development of the internal genital tract in the male?
Testosterone
Mullerian inhibiting factor
There are 2 primitive genital tracts: Wolffian and Mullerian ducts. Which duct contributes to male and female genital tracts respectively?
Males = Wolffian Females = Mullerian
Without stimulation by testosterone + Mullerian inhibiting factor, what develops in the male?
Internal genital tract resembling that of a female
The testes develop in the abdominal cavity but descend into the scrotal sac before birth. Why?
Lower temperature outside the body facilitates spermatogenesis
What is cryptorchidism?
Undescended testes, resulting in reduced sperm count and increased risk of testicular cancer
What does testicular descent depend on?
Androgenic drive
Where does spermatogenesis occur?
Seminiferous tubules
Where is testosterone secreted from?
Leydig cells
List the function of Sertoli cells
Form blood-testis barrier (protection) Provide nutrients for developing cells Phagocytosis Secrete seminiferous tubule fluid Secrete androgen-binding globulin Regulate FSH levels through inhibin
Where does LH act in the male?
Leydig cells - regulate testosterone levels
Where does FSH act in males?
Sertoli cells - enhances spermatogenesis
What are the 3 main categories of causes of male infertility?
Idiopathic (most common cause)
Obstructive
Non-obstructive
List some obstructive causes of male infertility
Cystic fibrosis (vas deferens defect)
Vasectomy
Infection
List some non-obstructive causes of male infertility
Cryptorchidism Infection Radiation (chemo/radiotherapy) Testicular tumour Genetic: Klinefelter's Semen structure abnormality Systemic/endocrine disorders
List some pituitary causes of male infertility
Tumours
Acromegaly
Cushing’s disease
Hyperprolactinaemia
List some hypothalamic causes of male infertility
Tumour
Increased exercise
Kallmann’s syndrome
Anorexia
Which drug when abused is notorious for causing male infertility?
Steroids
What would be assessed on genital examination in a male with infertility?
Testicular volume (normal = 12-25ml) Presence of vas deferens + epidydimis Penis Urethral orifice Presence of swellings/varicocele
What 5 domains are assessed on semen analysis?
Volume Density (number of sperm) Motility (how many are moving) Progression (how well they move) Morphology
What extrinsic factors may cause abnormality in semen analysis?
Completeness of sample Period of abstinence from sex Conditions during transport Time delay Health of the man
How would testicular volume, secondary sexual characteristics, endocrine hormones and structure of vas deferens be affected in obstructive male infertility?
All normal
Vas deferens may be absent
How would testicular volume, secondary sexual characteristics, endocrine hormones and structure of vas deferens be affected in non-obstructive male infertility?
Low testicular volume
Reduced secondary sexual characteristics
High endocrine hormones
Vas deferens present
List some lifestyle improvements that can help male infertility
Frequent sex, 2-3x a week Avoid lubricants (toxic to sperm) Less than 4 units of alcohol a week Stop smoking BMI less than 30 Avoid tight underwear, saunas/hot baths
When is ICSI indicated over IUI?
IUI - low sperm count
ICSI - very low sperm count
What is the success (pregnancy) rate of IUI and ICSI?
IUI = 15% ICSI = 30%
When is surgical sperm aspiration indicated?
Azoospermia (very low sperm count)
What is the success (pregnancy) rate of surgical sperm aspiration?
95% in obstructive
50% in non-obstructive
If IUI, ICSI and sperm aspiration fail, what is the next option?
Donor sperm
