Multifetal Gestation (Moulton)

Question 1

Multiple gestation

Answer 1

any pregnancy in which two or more embryos or fetuses occupy the uterus simultaneously

Question 2

Dizygotic twins (fraternal)

Answer 2

two separate ova are fertilized by two separate sperm; each will have its own amnion, chorion and placenta

Question 3

Monozygotic twins 0-3 days of cleavage

Answer 3

dichorionic, diamniotic

Question 4

Monozygotic twins 4-8 days of cleavage

Answer 4

monochorionic, diamniotic

Question 5

Monozygotic twins 9-12 days of cleavage

Answer 5

monochorionic, monoamniotic; most dangerous since there are not separating amnions; high risk for cord entanglement and net mortality

Question 6

Monozygotic twins >13 days of cleavage

Answer 6

conjoined twins

Question 7

Craniopagus

Answer 7

conjoined twins joined at the cranium (2%)

Question 8

Thoracopagus

Answer 8

conjoined twins joined at the chest wall (30-40%) most common

Question 9

Ischiopagus

Answer 9

conjoined twins joined at the coccyx and sacrum (6%)

Question 10

What is the most important step after diagnosing twins

Answer 10

determination of zygosity

Question 11

Dizygotic twins on US

Answer 11

different genders; visualization of thick amnion-chorion septum; “peak” or “inverted V” sign at the base of the septum

Question 12

Most common inter-placental vascular anastomoses in conjoined twins

Answer 12

arterial-arterial

Question 13

Twin Twin Transfusion Syndrome (TTTS)

Answer 13

uncompensated arterial-venous anastomoses; blood flow going from one twin to the other;
donor twin - hypovolemia
recipient twin - hypervolemia
**both twins are at risk for demise from heart failure; poor prognosis

Question 14

Treatment of Twin Twin Transfusion Syndrome (TTTS)

Answer 14

laser photocoagulation

Question 15

Acardiac twin

Answer 15

fully formed lower extremities; no anatomic structures cephalad of the abdomen

Question 16

Retained dead fetus syndrome

Answer 16

single fetal death in utero; if gestation < 12 weeks, the dead fetus is reabsorbed “vanishing twin syndrome”; >12 weeks, twin shrinks and is called fetus papyraceus

Question 17

fetus papyraceus

Answer 17

single fetal death in utero; >12 weeks gestation, twin shrinks and is called fetus papyraceus

Question 18

When should monoamniotic twins be delivered?

Answer 18

32 weeks

Question 19

Vertex-transverse & vertex-breech presentation

Answer 19

often delivered C-section

Question 20

Breech-breech & breech-vertex

Answer 20

always delivered C-section

Question 21

Average delivery for triplets

Answer 21

33 weeks; C-section

Question 22

Average delivery for quadruplets

Answer 22

29 weeks; C-section

Question 23

What is the most common malpresentation in twins

Answer 23

breech; most common factor is prematurity

Question 24

Which forceps are used when a baby is in a breeched position?

Answer 24

Piper forceps

Question 25

Brow presentation

Answer 25

presenting fetus is between the facial orbits and anterior fontanelle; frontal bones are the point of designation

Question 26

Face presentation

Answer 26

full extension of the fetal head and neck with occiput against the upper back

Question 27

Compound presentation

Answer 27

fetal extremity is found prolapsed alongside the fetal head (like raising their hand)

Question 28

External Cephalic Version (ECV)

Answer 28

applying pressure to the mother’s abdomen to turn the fetus in either a forward or backward somersault; indicated 36 weeks gestation, not in labor; contraindicated in placenta previa