L10: Assisted Reproducitve Treatments Flashcards
Where does fertilisation occur
In the ampulla of the uterine tube
How does the fertilised egg go down to the uterus
Peristalsis
What does the fertilised egg become at day 5
Blastocyst
Explain the stages of cells the fertilised egg becomes during cleavage
Zygote Blastomere 4 cell 8 cell 16-32 cell = morula Blastocysts
What happens to the blastocyst at day 6
Hatches away from the zona pellucida
Describe what happens in intra-uterine insemination
1) male partner gives sperm
2) sperm is placed into a catheter with a syringe
3) catheter is passed into the uterine cavity
4) sperm is injected
When is it important to carry out intrauterine insemination for fertilisation to occur
When ovulation has occurred
How do we check if ovulation is going to occur
By LH surge
Is the intra-uterine insemination NHS funded
No
At what circumstances is intra-uterine insemination recommended
- partner cannot have a sexual intercourse
- male has HIV
- if partners are from same sex so donor sperm is required
If the male patient has HIV what happens to the sperm
Washed
To stimulate the ovaries what can we use
FSH
To trigger an LH surge what hormone can we use
HCG trigger
After the intra-uterine insemination what is required after 2 weeks to see if the patient is pregnant
Pregnancy test
What are the disadvantages of intra-uterine insemination
Low success rate
Can result in multiple pregnancy as we aim for 3 dominant follicles with FSH
Expensive
Invasive method
When might IVF be recommend
- tubal blockage: sperm cannot meet egg
- PCOS
- unexplained fertility: everything is normal
- endometriosis
- increased age
- no egg due to chemotherapy so egg donor with IVF
- patients with no uterus: IVF occurs in host surrogacy
Describe the process that occurs in IVF
1) we turn the HPG axis off by suppressing the pituitary via GNRH antagonist
2) LH/FSH is not produced
3) we then develop multiple follicles at the same time
4) we give HCG to trigger LH surge to allow for final egg maturation
5) we use a needle to aspirate the fluid
6) examine fluid and collect the eggs
7) oocyte and sperm fertilised on a dish
8) sperm has to fertilise the egg by penetrating the zona pellucida
9) blastocyst forms
10) blastocyt in inserted to the uterus
11) mimic the function of corpus luteum so we give progesterone to cause secretory changes of the endometrium
12) do a pregnancy test after 2 weeks
Why do we use HCG to cause an LH surge (think about its structure)
HCG is homologous in its structure to LH, using LH is expensive
What is intracytoplasmic sperm injection (ICSI)
When the sperm is directly inserted into the cytoplasm of the oocyte instead of allowing it to penetrate the zona pellucida
When is ICSI recommended
If the sperm has dysfunction in motility and number count to penetrate the the egg
When we fertilise the egg why do we wait for 5 days before inserting it into the uterus straight away
To allow:
Embryonic genome switching
Figure out the best blastocyst
What are the disadvantages of IVF
Multiple pregnancy Ovarian hyper stimulation syndrome Oocyte collection risk : injury to the bladder Expensive Invasive
What is ovarian hyper stimulation syndrome
Overstimulating the ovaries that causes production of vasoactive substances
If patients want to preserve sperm and eggs what liquid do we use
Nitrogen and cytoprotectant
Which female patients would require an donated oocyte
Ovarian failure Turners syndrome (XO) Loss of ovaries Premature menopause Menopause due to increased age
Which patient would require sperm donor
Testicular failure
Obstructive
Klinefelters syndrome (XXY)
Deletion of Y chromosome
