In Vitro Fertilization - RM Flashcards
What is the definition of infertility?
inability to conceive within 12 months without contraception
What are causes of male infertility? (4)
low or no sperm count
problems with quality of sperm
motility issues
genetic mutation of sperm
What are causes of female infertility? (5)
failure to ovulate regularly or at all low supply of egg-producing follicles blocked or damaged fallopian tubes endometriosis uterine problems--fibroids, polyps, structural problems
How do drugs, smoking, pollution and radiation contribute to infertility?
contribute to oxidative stress and spermatozoal dysfunction and infertility
What systemic pathologies can lead to infertility due to oxidative stress?
diabetes, cancer, systemic infection
What happens with ovarian aging?
- FSH increases but doesn’t induce E2 release from ovaries
- decreased quality of eggs as well as decreased numbers
What is IUI? Why is it done?
intrauterine insemination, want to avoid IVF if possible
What is GIFT? Can it be done more than once?
gamete intrauterine fallopian tubes, put egg and sperm in the fallopian tubes and let them find each other
-can’t be done again because the surgery damages the fallopian tubes
What is the swim up technique?
centrifuge sperm, put in culture media so they start swimming and inject the concentrated fluid with sperm in it during super ovulation
What is the column technique?
aspirate the most motile pserm from the column and put into uterus
Why shouldn’t you take aspirin or ibuprofen etc when you are trying to get pregnant?
prostaglandins help the egg drop so you don’t want to inhibit them
Why do you want to inhibit the hypothalamic-pituitary-ovarian axis?
suppressing it prevents negative feedback on oocyte development and induces as many eggs being released as possible for IVF
What is the long protocol for suppression of the hypothalamic-pituitary-ovarian axis? short protocol?
Long protocol–GnRH agonists (eventually causes downregulation of receptors and desensitization to LH/FSH)
short protocol–GnRH antagonists (cetrorelix, causes immediate drop in LH/FSH production)
What are the risks in oocyte retrieval? What does the ovaries produce that cause this risk?
risk ovaries swelling up and casing hemoconcentration, which increases the risk of coagulation in vascular systems and clots/pleural effusions
ovaries produce VEGF
What is ICSI? When is this usually done?
intracytoplasmic sperm injection, when males have low sperm count because it injects a single motile sperm directly into the cytoplasm of the egg
At what stage is preimplantation genetic diagnosis done?
blastomere stage, one cell of the blastomere taken because at this stage all the cells are totipotent and each one can all develop into identical embryo
What technique can be used for patients with absent Mullerian ducts or uterus, anatomically abnormal uterus, or medical contraindication to pregnancy?
gestational carriers/surrogacy
What is hCG used as a trigger for? What does it mimic that allows it to be used for this?
ovarian hyperstimulation
mimics LH surge to cause extrusion of eggs but has a longer halflife than LH because of the sugar molecules attached
At what stages can you transfer a developing embryo after insemination? What is the advantage of each?
4 cell stage or 8 cell stage–plays it safe because embryo may not make it till day 5 in vitro
blastocyst stage–hardier than 4 or 8 cell stage, corresponds with normal physiology since zygote usually reaches uterus in 5 days in vivo
Why do you want to make sure there are only 2 pronuclei after fertilization?
have to make sure it wasn’t a polyspermy fertilization
Why is a hole made in the zona pellucida in pateints with multiple IVF failures?
the blastocyst must hatch from the zona pellucida and making the hole helps blastocyst expand out from it
How far from the fundal portion of the uterus should you deposit an embryo?
about 1 cm, because if its too close to fallopian tubes it may become ectopic
How do you determine how many embryos to transfer?
age of the mother, embryo quality
When is the risk of multiple pregnancies higher?
with younger moms
What is the limiting factor for embryo quality, age of the egg or age of the uterus?
age of the egg
What is the purpose of oncofertility?
removal of ovarian tissue to freeze eggs or fertilize them and freeze embryos so you can treat cancer without worrying about infertility after treatment
What occurs in 3 parent embryos? What disease is this good for avoiding?
- healthy nuclear DNA from mother with mutated mitochondrial DNA put in enucleated donor egg cell with healthy mitochondrial DNA and fertilized with father’s sperm
- avoids mitochondrial disorders passing on through children
How is cloning done?
- take the nucleus of a somatic ell with complete genetic complement
- put that nucleus in an enucleated egg cell
- trigger it to divide so all 46 chromosomes come from that 1 source
- embryos grow really fast because that somatic cell has already imprinted
What is clomifene?
selective estrogen receptor modulator used to induce ovulation
