Twin Pregnancy

Question 0

These are twins which are derived from two completely separate ova, each fertilized by a different sperm. In essence, these are simply brother or sisters that shear the same uterus at the same time, never identical, fraternal twins

Answer 0

Dizygotic twins

Question 1

These are twins divided from the division of one fertilized ovum or zygote. By definition, they are identical, always the same gender

Answer 1

Monozygotic twin

Question 2

Dizygotic twins comprises ______ or about ______% of all twins occurring in one out of 80 conceptions, lowest risk of all twins because they have their own ______ and ______

Answer 2

Two thirds or 66%

Placenta and amniotic sac

Question 3

Dizygotic twins are more common in ______ women than Asians, tends to be inherited trait

Answer 3

African

Question 5

The ______ sign is used to diagnose a dizygotic/dichorionic/diamnionic twin pregnancy in the second and third trimester, this simply means that one placenta dissects between the other placenta and amniotic sac

Answer 5

Twin peaks

Question 6

what does the number of chorions, placentas, amnions or amnionic sac depend on in monozygotic twins?

Answer 6

when exactly the zygote divided

Question 7

if the morula divided in the first ______ days, each fetus will have its own chorion and its own amnion (dichorionic/diamnionic) there will be two widely separated gestational sacs in the first trimester, no twin peak sign until the second and third trimesters of dichorionic/diamnionic twin pregnancies

Answer 7

0-3 days

Question 8

if the preimplantation blastocyst divides on day ______ they will share a placenta but have two separate amnionic sacs (monochorionic/diamnionic) on TV you will see a thin dividing membrane in 1st trimester (the amnionic membrane); one placenta; no twin peak at all

Answer 8

4-7 days

Question 9

if the blastocyst divides on days ______, monochorionic/monoamnionic will result; no dividing membrane at all; in 1st trimester the twins are close in relationship to one another**

Answer 9

8-12

Question 10

deciding the amnionicity and chorionicity is best done in the first trimester with ______ sonography

Answer 10

transvaginal

Question 11

if the morula divides after day ______, conjoined twins is the result

Answer 11

13

Question 12

what are the conjoined twin sight of union descriptions of; omphalopagus, pyopagus, ishshiopaus, and craniopagus

Answer 12

omphalopagus- xiphoid to umbilicus
pyopagus- sacrum
ishshiopaus- ischium/pelvis
craniopagus- head

Question 13

what are the clinical findings of twin pregnancies?

Answer 13

higher beta hCG levels, higher maternal serum alpha-fetoprotien levels, and bigger uterine size/large for dates

Question 14

what are the maternal complications of twin pregnancy?

Answer 14

hypertension/preeclampsia and eclampsia, preterm labor/premature delivery, anemia, postpartum hemorrhage (because of inadequate contractions), and placenta abruption

Question 15

what are the fetal complications of twin pregnancy?

Answer 15

prolapse or entanlement of the cord and cord knots (in monoamnionic twins) interuterine growth retardation due to placental insufficiency and difficult delivery

Question 16

when there are higher levels of multiples, a patient and their physician may elect to do selective ______ in order to lower the risks to the fetuses and their mother

Answer 16

reduction

Question 17

in terms of in vitro fertilization, why will most fertility doctors not implant more than 2 fertilized eggs?

Answer 17

one of those fertilized eggs may split and result in an identical pair set of twins plus the other fetus, many agree triplets are already a risk

Question 18

this occurs with demise of one twin, usually because one twin had a chromosomal abnormality. You will see that one twin is bigger than the other within normal fetal heartbeat and the other is smaller and has no fetal heartbeat; no treatment for this; demised twin will resorb into the uterine wall

Answer 18

vanishing twin; sometimes there is small amounts of vaginal bleeding

Question 19

this syndrome affects only monozygoitc twins because there is a shared placenta, it results because of anomalous development of vascular connections between the shared placenta; most serious form-vein anastomoses shunts blood away from the donor twin, to the recipient twin

Answer 19

twin transfusion syndrome/poli-oli sequence

Question 20

in twin transfusion, how is the recipient twin affected?

Answer 20

polyhydramnios, hydrops-edema, pleural effusion, ascites, large for dates

Question 21

in twin transfusion, how is the donor twin affected?

Answer 21

oligohydramnios, small for dates, “stuck” twin (in small amount of fluid and cant move)

Question 22

this is the passage of thromboplastic material or blood clots from a dead monochorionic twin to the remaining live twin through the shared intraplacental vasculature; can result in neurologic, gastrointestinal, or genirourinary deficits in the live fetus

Answer 22

twin embolization syndrome

Question 23

what are the findings for twin embolization syndrome?

Answer 23

interuterine death of one twin, hydrops fetalis in the live twin, polyhydramnios, intra-cranial hemorrhage, porencephaly, ventriculomegaly, enlarged echogenic kidneys in live fetus

Question 24

this is a bizarre form of monozygotic, monochorionic twins in which the acardiac twin has no direct vascular connection with the placenta. arterial anastomosis shunts blood from the donor twin to the acardiac twin

Answer 24

twin reversed arterial perfusion (TRAP) or sequence/acardiac twinning/para biotic twin

Question 25

in TRAP, the donor twin is called the ______ twin and is usually sonographically normal except for the enlarged heart or cardiomegaly; this twin could develop heart failure and hydrops due to the increased burden of being the heart for both twins

Answer 25

pump

Question 26

US findings in the acardiac and pump twin in TRAP is?

Answer 26

acardiac twin- multiple structural anomalies and no cardiac motion, still grows and moves, anencephaly or small head, limited upper extremity development, and cystic hygroma
the pump twin-hydrops fetalis