Assisted Reproduction Flashcards
What is important to understand for ART?
Menstrual physiology and fertilisation implantation
What surges during ovulation and what are the results?
FSH and LH surge. LH surge stimulates the release of the oocyte into the fallopian tube.
What is left over after ovulation and what does it mainly produce?
The corpus luteum is left over and it mainly produces progesterone.
What does progesterone do?
Progesterone causes secretory changes to the endometrium, allowing for implantation of a fertilised oocyte.
What happens at the end of the 14 days after ovulation?
Progesterone and oestrogen levels are reduced, leading to the breakdown of the endometrium and menstruation.
What does the fall of progesterone and oestrogen do to the HPG axis?
It causes a reciprocal increase in FSH from the anterior pituitary.
What does FSH and LH stimulate?
FSH stimulates granulosa cells, and LH stimulates theca cells, leading to the growth of follicles.
What happens to the dominant follicle?
The dominant graphene follicle produces high levels of oestrogen and progesterone, leading to a positive feedback loop and LH surge.
What hormone does the hypothalamus produce and how frequently?
The hypothalamus produces GnRH in a pulsatile manner, causing the release of FSH and LH from the anterior pituitary.
What is the concentration of LH and FSH secreted dependent on?
It is dependent on feedback from oestrogen and progesterone levels.
What do regular periods indicate?
Regular periods indicate that a woman is ovulating.
What changes occur to the endometrium during the menstrual cycle?
In the first half, the endometrium proliferates. At ovulation, the corpus luteum produces progesterone, causing secretory changes.
What can happen in unprotected sex?
It is possible for sperm to meet the secondary oocyte at the ampulla to produce an embryo.
Where does the embryo remain for the first few days?
The embryo remains in the fallopian tube for the first 4-5 days and is wafted down towards the uterine cavity via peristalsis.
What is the embryo once reaching the endometrial cavity?
Once it reaches the endometrial cavity, it is already a blastocyst (day 5).
Why does the endometrium need to be secretory?
The endometrium needs to be secretory to be receptive to the blastocyst.
Describe the process of IUI.
A sperm sample is collected, placed in a catheter, and injected into the uterine cavity.
What is important for IUI?
Timing is crucial; LH surge can be tested using urinary kits to time the injection of sperm.
What are the NICE indications for IUI?
Inability to have sexual intercourse, need for sperm washing, and same-sex couples using donor sperm.
What are the 4 steps of IUI?
- IUI can be done with or without ovarian stimulation. 2. With or without HCG triggering. 3. Sperm preparation and insemination. 4. Pregnancy test 2 weeks later.
What are the problems involved with IUI?
Low success rate, risk of multiple pregnancy, cost, and invasiveness.
When is IVF done?
Indications include anovulatory conditions, tubal disease, endometriosis, unexplained infertility, male factor infertility, and other failed treatments.
What are the steps of IVF?
- Counselling and consenting. 2. Pituitary suppression. 3. Ovarian stimulation. 4. HCG triggering. 5. Oocyte retrieval.
How is insemination done in IVF?
Insemination can be done using IVF or ICSI.
How long are embryos cultured for?
Embryos are usually cultured for 2, 3, or 5 days.
What is luteal support and why is it important?
Luteal support mimics corpus luteal function by providing progesterone to prepare the endometrium for embryo implantation.
What is the final stage of IVF?
A pregnancy test is done 2 weeks after embryo transfer to check for implantation.
What are the problems in IVF?
Multiple pregnancies, ovarian hyperstimulation syndrome, risks during oocyte collection, long-term maternal risks, cost, chances of live birth, and invasiveness.
When is ICSI used?
ICSI is used in cases of sperm dysfunction or failure of fertilisation in IVF.
How is sperm retrieved for ICSI?
Surgical sperm retrieval is required if there is obstruction of the vas deferens.
What is perm dysfunction?
Problems with sperm concentration, morphology or motility.
How is sperm retrieved?
Surgical sperm retrieval is required e.g. if there is obstruction of vas deferens.
Where is sperm collected from?
Sperm is collected from epididymis or testicle itself.
What are the benefits of ICSI if sperm are normal?
There is no demonstrable benefit to using ICSI if sperm parameters are normal – so IVF is default as it allows for natural selection.
When are embryos cultured?
Culture of embryos occurs 5-6 days post oocyte collection.
What significant hurdles does the development of the blastocyst pass through?
- Switching on of embryonic genome 2. Past stages of totipotency to first differentiation.
What does the switching on of embryonic genome allow for?
This allows for non-invasive embryo selection.
How are embryos transferred?
Select best embryo, then use a speculum inside vagina and thread catheter to inject embryo inside the uterine cavity.
How can oocytes and sperm be preserved?
Oocytes and sperm can be preserved using liquid nitrogen and cryoprotectant.
Why is cryopreservation useful?
This is useful to continue having embryo transfer without needing further ovarian stimulation.
When is cryopreservation also done?
This is also done if men or women are diagnosed with cancer or any other medical condition affecting future fertility.
How successful is sperm + oocyte cryopreservation?
Sperm cryopreservation is very successful. Oocyte cryopreservation is more difficult and less successful.
When are donated oocytes used?
Used in women who have: 1. Ovarian failure 2. Premature menopause 3. Turner’s syndrome 4. Low egg reserves 5. Carrier of inheritable disease 6. Surgical loss of ovaries.
When is donated sperm required?
- Azoospermia 2. Male partner is a carrier of inheritable disease.
What is Azoospermia?
Azoospermia includes: 1. Testicular failure 2. Obstructive/absence of vas deferens 3. Microdeletions of Y.
What is the Human Fertilisation and Embryology Authority?
They are the UK’s independent regulator overseeing fertility treatment and research.
What does the HFEA do?
The HFEA licenses fertility clinics, performs regular inspections, and provides success rates on their website.
What is pre-implantation genetic diagnosis?
Removal of one or two cells from the early embryo for genetic analysis.
What is pre-implantation genetic diagnosis used for?
To check for single gene disorders & balanced translocations such as CF, Huntington’s disease, and Sickle cell disease.
