Flashcards in Unit 7 - In Vitro Fertilization Clinical Correlation Deck (16)
what is the definition of infertility?
inability to conceive within 12 months without contraception
-affects ~10-15% of the general population
-10-20% of couples have "unexplained" infertility (evaluation fails to identify the problem)
common causes of male infertility
-low/no sperm count
-problems with quality of sperm (affected by drugs, smoking, pollution/radiation, diabetes, cancer, systemic infection)
-genetic mutation of sperm
common causes of female infertility
-failure to ovulate regularly or at all
-low supply of egg-producing follicles
-blocked/damaged Fallopian tubes
-uterine problems (fibroids, polyps, structure)
when does fertility decline?
as early as age 27
-significant decline seen at age 35 and beyond
-spontaneous pregnancies are rare after 45
what are 4 possible treatments for infertility?
1. ovulation induction (clomiphene citrate, DA agonists, pulsatile GnRH, aromatase inhibitors, gonadotropins)
2. reproductive tract surgery (microtuboplasty, etc.)
3. intrauterine insemination
4. assisted reproduction (in vitro fertilization, GIFT)
what happens in intra uterine insemination (IUI)?
semen is centrifuged to concentrate sperm within supernatant (need supernatant b/c raw sperm would cause allergic RXN)
-supernatant is injected into uterus directly
what happens in in vitro fertilization?
1. patient selection (male factor, tubal factor, etc.)
2. hypothalamic-pituitary-ovarian down regulation and suppression (either long protocol GnRH agonists or short protocol GnRH antagonist)
3. controlled ovarian hyperstimulation (to increase mature follicles, but beware or else will rupture or twist ovary, causing emboli or hemorrhage)
4. oocyte retrieval
5. preimplantation embryo culture
6. embryo transfer
what are specialized ancillary IVF procedures? (6)
1. assisted embryo hatching
2. itra cytoplasmic sperm injection (ICSI)
3. preimplantation genetic diagnosis (PGD) to make sure mutations in gametes aren't transferred
4. oocyte/embryo cryopreservation
5. oocyte/embryo donation
6. gestation carriers (surrogacy)
what's the difference between long protocol and short protocol HPO?
long: GnRH agonists; initial flare of LH and FSH over two weeks, but then downregulation and desensitization by internalizing the receptors
short: GnRH antagonists; very quickly block LH and FSH
what is the hCG trigger?
1. give very high FSH levels (either long-lasting or in successive shots), to cause many follicles to mature at the same time
2. give hCG, which acts like an LH surge, to allow all the mature eggs to ovulate at once
what is ICSI?
intra cytoplasmic sperm injection
how to decide the number of embryos to transfer?
determined by age of mother and embryo quality
40 = 5
for patients with 2+ failed IVF cycles, or a poor prognosis, add more based on clinical judgement
what are options for excess embryos? (4)
1. freeze embryos
2. donate for research/stem cells
3. embryo adoption
what are some gestational surrogacy medical indications? (5)
1. uterus absent (congenital or iatrogenic)
2. anatomically abnormal uterus
3. medical contraindication to pregnancy
4. recurrent pregnancy wastage and loss
5. repeated IVF failures with good embryos
what are clinical indications for preimplantation genetic diagnosis (PGD)?
-single gene defects
-advanced maternal age (aneuploidy)
-repetitive IVF failure
-recurrent pregnancy loss