Lect 8: In vitro Fertilization

Question 1

What is Infertility?

Answer 1

the inability to conceive within 12 months without contraception

Question 2

Common causes of male infertility

Answer 2

low sperm count
problems with quality of sperm
motility issues
genetic mutation of sperm

Question 3

Common causes of female infertility

Answer 3

failure to ovulate regularly or at all
low supply of egg-producing follicles
blocked or damaged Fallopian tubes
uterine problems (fibroids, polyps)

Question 4

Ovarian Reserve

Answer 4

peaks in early fetal life (5-7 millon gametes at 20 wks of birth)
by the time you reach puberty you are down to 400,000
fertility can begin to decline by age 27
significant decline seen at age 35 and >
by age 45 spontaneous pregnancy are rare

Question 5

Treatment of Infertility

Answer 5

1. ovulation induction
2. reproductive tract surgery (for damaged tubes)
3. intrauterine insemination (IUI)
4. assisted reproduction (IVF, GIFT)

Question 6

Intrauterine insemination (IUI)

Answer 6

Two techniques: to concentrate sperm
swim up specimen
column technique

Question 7

Prostaglandins

Answer 7

don’t take Ibuprofin can retard ovulation

Question 8

What is the purpose of Down regulation of the Hypothalamic-Pituitary-ovarian axis (HPO)

Answer 8

during the menstrual cycle the brain knows when th one follicle is matured and is ready to extrude it. However, they want more than one egg so they give meds to bypass this axis

Question 9

What is the Long protocol?

Answer 9

given GnRH agonists

Question 10

What is the short protocol?

Answer 10

given GnRH antagonists

Question 11

Controlled ovarian hyperstimulation?

Answer 11

to get as many eggs

Question 12

What are some examples of apecialized ancillary IVF procedures?

Answer 12

Assisted embryo hatching
Intra Cytoplasmic Sperm Injection (ICSI)
Preimplantation Genetic Diagnosis
Oocyte and Embryo Cryopreservation
Oocyte and Embryo Donation
Gestational Carriers (Surrogacy)

Question 13

Mullerian agenesis

Answer 13

the Mullerian ducts are two tubes that fuse together to form the fallopian tubes, uterus and upper vagina. They have ovaries and can produce eggs that can be transferred to a surrogate

Question 14

H-P-O Axis

Answer 14

arcuate nucleus produces GnRH which secrete it in pulses. Starts during puberty at night. This gets released and stimulates the gonadotrophins (FSH, LH). LH stimulates Theca cells to produce androgens and FSH will stimulates the granulosa cells to upregulate aromatase which converts androgens (testosterone to beta-estradiol). Need both cells types. They feedback on the brain to have –/+ impact

Question 15

H-P-O down regulation & suppression

Answer 15

GnRH agonists you get a flare effect but overtime it gets desensitized where there is activity to stop the production of LH & FSH
==>long protocol

Question 16

H-P-O down regulation & suppression

Answer 16

GnRH antagonist are competitive inhibitors of the receptor causing immediate block of FSH & LH
==>short protocol

Question 17

GnRH Analogs

Answer 17

can make antagonist or agonist

Question 18

hCG Trigger

Answer 18

bombarding the ovaries with lots of FSH to produce as many eggs as possible. Need hCG because it binds to the same receptor as LH does. LH surge causes ovulation. hCG mimics LH surge inducing ovulation. Then you retrieve this egg. hCG is also produced by the embryo as well. hCG has a longer half life due to sailic acid (a sugar molecule)

Question 19

Oocyte insemination (2)

Answer 19

1. standard oocyte insemination

2. ICSI- direct injection of the sperm into the oocyte allowing them to combine and divide

Question 20

Oocyte insemination - blastocyst

Answer 20

After the cell divides you transfer anywhere between the 4-8 cell stage. Blastocyst is a day 5 embryo. Day 6 it implants. Problem is that if you are Day 3 and the embryo is moving along nicely yo may not get to blastocyst stage and have no embryo. It depends on the amount of eggs that the person has to work with

Question 21

ICSI

Answer 21

directly injecting the sperm into the egg

==>2PN stage (two pronuclei stage one from mom and one from dad)

Question 22

Embryo Transfer

Answer 22

directly injecting the egg the egg into the uterus under ultrasound

Question 23

Options for Excess Embryos

Answer 23

freeze embryos
donate for research/stem cells
embryo adoption
discard

Question 24

Limiting Factor

Answer 24

is the age of the egg, not the mother

Question 25

PGD- preimplanatation genetic

Answer 25

to see if you have any genetic disorders

Question 26

Three parent Embryos

Answer 26

using mitochondrial nucleus adding to an normal cell. Transplant that nucleus to another cell than fertilizing that egg with a sperm

Question 27

Artifcial Gametes

Answer 27

using stem cells to become sperm and eggs and combine then to make an individual

Question 28

Oncofertility

Answer 28

noble.