Assisted Reproductive Technology

Question 1

What are the 4 types of infertility treatment?

Answer 1

1. surgery
2. drug therapy
3. insemination
4. ART (assisted reproductive technology); what we will talk about in this lecture.

Question 2

What are the types of ART (assisted reproductive technology)?

Answer 2

• IVF
• GIFT (gamete intrafallopian transfer); old and not done anymore.
• ZIFT (zygote intrafallopian transfer); old and not done anymore.
• ICSI (intracytoplasmic sperm injection)
• AH (assisted hatching)
• PGF (preimplantation genetic diagnosis)

Question 3

So what do ART procedures involve?

Answer 3

• any procedures where we directly retrieve the eggs from the ovaries, and work with them along with sperm in the lab.

Question 4

What was IVF originally developed as?

Answer 4

• a means for bypassing the fallopian tubes in women whose tubes were blocked.

Question 5

What are the indications for IVF?

Answer 5

• tubal disease
• male factor infertility
• unexplained infertility
• endometriosis
• PCOS
• repeat pregnancy loss

Question 6

*** What are the steps of IVF?

Answer 6

1. ovarian stimulation to develop follicles.
2. ultrasound guided oocyte retrieval.
3. insemination/fertilization (in-vitro).
4. embryo transfer to uterus (delicately under ultrasound guidance).

Question 7

What is the embryo development prior to transcervical embryo transfer (IVF-ET)?

Answer 7

1. pronuclear stage= 1 day after retrieval.
2. 2 cell stage= 1.5 days
3. 4 cell stage= 2 days
4. 8 cell stage= 3 days
5. morula= 4 days
6. early blastocyst= 5 days
7. expanded blastocyst= 5.5 to 6 days

Question 8

*** What is intracytoplasmic sperm injection (ICSI)?

Answer 8

• assisted fertilization technique whereby we inject a SINLGE SPERM into the CYTOPLASM of the EGG, bypassing the potential sperm’s unsuccessful attempt at getting through the zona pellucida.

Question 9

What are the indications for intracytoplasmic sperm injection (ICSI)?

Answer 9

• idiopathic fertilization failure (at least 1 prior IVF failure).
• known significant male factor (abnormal sperm count, motility or morphology).

Question 10

*** What is assisted hatching?

Answer 10

• assisted implantation technique, in which just prior to transfer, we use a lazer to break the zona pellucida (egg shell) of an already fertilized embryo.
• some embryos are not able to break this “egg shell” thus, this aids the embryo in its ability to implant in the uterus.

Question 11

What are the indications for assisted hatching?

Answer 11

• age greater than 38.
• diminished ovarian reserve.
• thick zona pellucida
• prior failed implantation

Question 12

What is embryo cryopreservation?

Answer 12

• freezing of embryos in reserve to use if other transplantation attempts fail.

Question 13

** What are the advantages of embryo cryopreservation?

Answer 13

• enhanced overall pregnancy rate PER RETRIEVAL.
• alternative to destruction of excess embryos (usually we get 8-10 eggs per retrieval).
• less expensive
• less invasive oocyte retrieval and anesthesia not necessary.
• decreased risk of OHSS.

Question 14

*** What is preimplantation genetic screening (PGS) and diagnosis (PGD)?

Answer 14

• screening for a genetic abnormality prior to implantation.
• aka only implanting those embryos without genetic defects.

Question 15

What are the indications for PDG?

Answer 15

• diagnosis of single gene defects (ex. sickle cell disease).
• prior chromosomally abnormal pregnancy (only transfer euploid embryos and not the aneuploid embryos).
• recurrent pregnancy loss (balanced translocation).
• family balancing (sex selection).
• age related infertility

Question 16

What were problems with biopsy of a 3 day embryo?

Answer 16

• chromosomal mosaicism (not all the cells may be the same).
• embryo damage by biopsy at 8 cell stage.
• inadequate cytogenetic methods.
• limited chromosomal assessment.
• embryos may have the ability to “self-correct.”
• we now biopsy at the blastocyst stage (day 5 or 6= 200 cells).

Question 17

What cells do we remove at the blastocyst stage?

Answer 17

• 4 to 8 trophectoderm cells (the placenta) not the inner cell mass

Question 18

What are the advantages of the blastocyst biopsy?

Answer 18

• comprehensive 23 chromosomal pair screening!
• trophectoderm biopsied (no known harm to embryo).
• multiple cells (4-6) analyzed.

Question 19

What are the indications for egg donation?

Answer 19

• advanced age
• poor egg quality (diminished ovarian reserve).
• absence of ovaries
• genetic oocytes

Question 20

Why is egg freezing becoming more successful?

Answer 20

• ultra-rapid freezing now reduces the risk of ice crystals forming and damaging the egg :)

Question 21

What are the indications for egg freezing?

Answer 21

• pts receiving gonadoxtoxic therapies for cancer in a young girl especially.
• genetic conditions (BRCA, Turner’s, Fragile X).
• unwilling to freeze embryos.
• elective or social egg freezing.