Twinning Softchalk

Question 1

When is ISCI most applicable?

Answer 1

Male factor infertility

removal of zona pellucida

Question 2

Egg donation most applicable?

Answer 2

Infertility associated with ovarian failure or diminished ovarian reserve. Maternally transmitted genetic diseases

Question 3

Gamete Intrafallopian Transfer

Answer 3

Egg and sperm deposited directly in oviduct.

Question 4

Zygote Intrafallopian Transfer

Answer 4

Fallopian tube transfer of embryo

Question 5

Embryo Cyropreservation

Answer 5

Early embryos resulting from IVF are preserved, transfer of four to eight cell embryos and blastocytes

Question 6

Oocyte Cyropreservation

Answer 6

Unfertilized eggs, challenging

Question 7

In Vitro Maturation

Answer 7

Immature oocytes and allowing completion of meiosis in vitro.

Question 8

Pre-implantation genetic diagnosis

Answer 8

3-5 days after in vitro fertilization
NO LATER THAN 8 CELL STAGE
analyzing for genetic disorder and sex
male embryo would be at risk for X linked disorder

Question 9

Risks of ART

Answer 9

multifetal gestation
prematurity or fetal growth restriction
rates of major congenital defects
placenta previa

Question 10

No differences between ART and natural conception

Answer 10

psychomotor development of preschool children

socio-emotional development

Question 11

Numbers for Twinning

Answer 11

1 in every 85 pregnancies
triplets 1 in 89x89
quadruplets 1 in 89x89x89
quintuplets 1 in 89x89x89x89
HILLIN'S LAW

Question 12

IVF pregnancies and twinning

Answer 12

37%

Question 13

Monozygotic Twins

Answer 13

single original embryo
0.4%
identical gene makeup

Question 14

Splitting at less than 8 cells (0-3 days)

Answer 14

Dichorionic, diamniotic
behave like dizyotic twins
two cell stage to morula stage
two identical blastocysts

Question 15

Morula stage (4-8 days)

Answer 15

single chorion and placenta, but seperate amnions, single placenta
monochorionic, diamniotic
potential for anastomosis between twins (one receiving most of nutrition)

Question 16

after blastocyst with inner cell mass (8-12)

Answer 16

common chorion and single amnion
monochorionic, monoamniotic
division of inner cell mass (embryonic disc)
complete division
risk for umbilical cords entanglement after 20 weeks, blood supply interupted

Question 17

Splitting of bilaminar embryonic dic (after 12 days)

Answer 17

conjoined twins. same amnion

Question 18

Dizygotic Twins

Answer 18

fraternal 
seperate oocytes produced during same mentstrual cycle
most frequent
increases with maternal age
genetic basis
three fetal membranes all seperate

Question 19

Rate of dizygotic twinnings

Answer 19

3x more in general population

more prominent in African populations

Question 20

Blastocyst implantation of dizygotic twins

Answer 20

Close together (placenta fusion) or far apart

Question 21

Anastomoses of vessels supplying two placentae complications

Answer 21

In utero death of one twin
twin-twin transfusion syndrom
twin-reversed arterial profusion (TRAP, less common)
cord entanglement (not related to anastomosis)

Question 22

In utero death

Answer 22

blood pressure of twin drops significantly, remaining twin at risk (heart failure to fill both circulator systems at once)
other twin may be killed by an embolism

Question 23

TTTS

Answer 23

twin to twin transfusion syndrom
monchorionic, diamniotic twins (10-20%)
unbalanced blood flow between twins

Question 24

Donor twin of TTTS

Answer 24

oligohydramnios
growth restriction
renal insufficiency

Question 25

Recipient twin

Answer 25

polyhydraminios
cardiac enlargement
eventually cardiac failure

Question 26

TRAP sequence

Answer 26

1 in 35,000 births

pump twin provides all the blood flow to acardiac/acephalic twin through anastomoses

Question 27

Pump twin risks

Answer 27

cardiac failure, 50-75% death, provides all blood flow to acardiac/acephalic twin

Question 28

Acardiac/acephalic twin

Answer 28

unable to survive without pump twin in TRAP

dies when pump twin dies

Question 29

Cord entaglement

Answer 29

monochorionic, monoanmnionic twin
most common complication
death of one or both twins if it interrups blood supply through umbilical cord

Question 30

Triplet variation

Answer 30

one zygote–identical
two zygotes-identical twins and singleton
three zygotes–different sexes or same sexes (no more similar than infants from three separate pregnancies)

Question 31

What type of oocytes are retrieved during IVF? When are they transferred into the mother?

Answer 31

Superovulation. Mature oocytes. Transvaginal retrieval. Fertilization in vetro. blastocyst stage. transcervical transfer into endometrial cavity.