Conception and Subfertility

Question 1

What is the male ejaculate formed of? (mention percentages) total volume: 1.5-5ml

Answer 1

Testicles and epididymes (5%) - Sperm
Seminal vesicles (46-80%) - fructose
Prostate gland (13-33%) - PSA
Bulbourethral and urethral glands (2-5%) - lubrication

Question 2

What is the the liquefaction time of the ejaculate? and the pH?

Answer 2

within 60 mins

7.2 pH

Question 3

What are the sperm essentials for fertilization?

Answer 3

1) Motility to swim against action of tubal cilia
2) Capacitation - changes to outer glycoprotein coat
3) Acrosome reaction to penetrate zona

Question 4

Describe the steps in fertilisation.

Answer 4

Occurs in the ampulla of the oviduct
Mature capacitated sperm meets metaphase II oocyte
Hyperactivation and acrosome reaction of sperm/zona penetration/binding to oolemma
Causes final maturation of oocyte/release of second polar body
Sperm entry/binding to oolemma causes calcium transients which:
Activate the oocyte for further development
Release cortical granules avoiding polyspermy

Question 5

What would happen if a dispermic results in an abnormal conceptus (e.g. triploid - 3 nuclei)?

Answer 5

This type of abnormal fertilisation will possibly result in an abortion

Question 6

What are the stages of embryo development?

Answer 6

Pronucleate   6-20 hr	
Cleavage       18hr-3 days
Compaction   3-4 days
Blastocyst      5-6 days	
(Hatching)      5-7 days

Question 7

Until what cell stage cycle, does the oocyte control change/mRNA production?

Answer 7

4-8 cell stage

Question 8

What part of the earyly embryo secretes hCG? (preg test)

Answer 8

Trophoectoderm

Question 9

When does implantation occur and what are the stages?

Answer 9

Around 7 days after ovulation
Upper part of uterus
Apposition, adhesion and attachment

Question 10

What is classed as infertility? What is the prevalence in western couples?

Answer 10

1-2 years of attempting pregnancy

1 in 6/7 western couples

Question 11

What is the average age of:
first pregnancy
menopause
IVF patients

Answer 11

First pregnancy - 31yrs
Menopause - 51yrs
IVF - 35 yrs

Question 12

What might be causes of infertility in females?

Answer 12

Ovulatory failure
Pelvic factor
Cervix mucus
Endometriosis
Tubal damage
Sperm problem
Unexplaiend

Question 13

What could cause problems with ovulation?

Answer 13

Polycystic ovaries
Endocrine anomalies (e.g. high basal LH, high androgens, insulin insensitivity)
Overweight

Question 14

What must you avoid if you are trying ovarian stimulation for IVF for more eggs?

Answer 14

OHSS - Ovarian hyper stimulation syndrome

Question 15

What does IVF involve?

Answer 15

Involves ovarian stimulation
Brings gametes together more reliably
Selects embryos for ‘quality’
Places them in the uterus
Cryopreserves additional ‘spare’ embryos
Does not fix the cause of infertility.

Question 16

What determines how many cycles of IVF a female can receive? (not age/infertility issues etc)

Answer 16

Postcode lottery

Question 17

Incidence of what increases in relation to maternal age?

Answer 17

Trisomy 21 - Down’s syndrome

Question 18

What might cause infertility in males?

Answer 18

Impotence (Psychosexual, drug induced, paraplegia etc…)
No sperm in ejaculate (azoospermia)
Not many sperm (oligozoospermia <15million/ml)
Poorly motile (asthenozoospermia <32% progressive)
Abnormal morphology (teratozoospermia <4% normal)
Non-viable (necrozoospermia)
Anti-sperm antibodies
Y chromosome microdeletions
Sperm DNA damage
Sperm do not bind to or fertilise egg

Question 19

How can you treat male infertility?

Answer 19

Correct any hormonal imbalances/blockages/psychological problems where possible
Obtain the best possible sample from ejaculate
If too poor, obtain best possible sample from surgical retrieval
If sperm available, apply treatments to female partner in order of least invasiveness/appropriate to any female factor of infertility and age
Intrauterine insemination
IVF
ICSI
5. If no sperm available, or ICSI declined, consider donor sperm.

Question 20

How often is ICSI (Intra cytoplasmic sperm injection) used in IVF cycles?

Answer 20

50%

Question 21

What is ICSI and how does it work?

Answer 21

Injection of one immobilised sperm into egg
Injected avoiding presumed position of oocyte spindle
~5% of oocytes do not survive
Fertilisation, embryo
development and pregnancy rates similar to IVF with normal sperm. Some increased abnormality rate, likely due to parental factors.

Question 22

What are the risks of fertility treatment?

Answer 22

Failure (~50% per cycle, age-dependent)
Over response of woman to stimulation drugs (OHSS or multiple ovulation)
Multiple pregnancy
Advanced maternal age pregnancy
Psychological/financial
Known risks of embryology processes (eg ICSI, sex chromosomal disorders, inheritance of infertility, possibly imprinting disturbances)
Unknown risks of embryology processes