Multiple pregnancy

Question 1

Monozygotic vs dizygotic

Answer 1

Mono - identical twins- single zygote
Dizygotic - non identical twins (2 zygotes)

Question 2

Monoamniotic vs diamniotic

Answer 2

Single shared amniotic sac vs two seperate sacs

Question 3

Monochorionic vs dichorionic

Answer 3

Single shared vs two seperate placentas

Question 4

which type of twins have the best outcomes

Answer 4

Diamniotic
Dichorionic
Each foetus has own nutrient supply

Question 5

When does the embryo seperate for dichorionic diamniotic twins

Answer 5

Before day 3/before implantation

Question 6

When does an embryo split to be diamnitoic (2 sacs) and monochorionic (1placenta)

Answer 6

Days 4-8 - splits stright after implantation

Question 7

When does an embyo split for twins to be monoamniotic and monochorionic (shared placenta and sac)

Answer 7

After day 8 - while after implatation

Question 8

When are twins noticed

Answer 8

Booking US

Question 9

What is the booking US

Answer 9

Gestational age
Number of placentas (chprionicity) + amniotic sacs (amnionicity)
Risk of Downs syndrome (as part of combined test)

Question 10

What sign is seen in dichorionic diamniotic twins?

Answer 10

Lambda sign or twin peak sign
Membrane between twins

Question 11

What sign is shown on US in monochorionic diamnitoic twins?

Answer 11

T sign
Membrane between the twins

Question 12

What is a lambda sign or twin peak sign?

Answer 12

Triangular appearance where membrane meets chorion (as it partially blends into membrane)
Indicated sepearate placentas

Question 13

What is the T sign

Answer 13

Membrane between twins abruptly meets chroion, gives T appearance
Indicates monochorionic twin pregnancy (single placenta)

Question 14

Complications of multiple pregnancy to mother

Answer 14

Anaemia
Polyhydrmainos
HPTN
malpresentation
Spontaneous preterm birth
Insturmental delivery or C section
Postpartum haemorrhage

Question 15

Multiple pregnancy risk to foetus and noenates

Answer 15

Miscarraige
Stillbirth
Foetal Growth restriction
Prematurity
Twin-twin transfusion sequence
Twin anaemia polycythaemia sequnce
Congenital abnormalities

Question 16

WHat is twin twin transfusion syndrome

Answer 16

A connection between the blood supply to the foetuses = one oetus is starved of blood, other is overloaded

Question 17

What can happen to the recipient in twin twin transfusion syndrome

Answer 17

Majortiy of blood received -> fluid overloaded
HF , polyhydraminos

Question 18

What happends to the donor in twin twin transfusion syndrome

Answer 18

Growth restricition, anaemia and oligohydraminos

Question 19

What is foeto-foetal transfusion syndrome?

Answer 19

Twin-twin transfusion syndrome in pregnancies with more than two foetuses

Question 20

Treatment for twin twin tranfusion syndrome

Answer 20

Laser treatment

Question 21

What is oligohydraminos

Answer 21

Not receiving enough fluid therefore not passing enough

Question 22

Why is the recepient twin polycythaemic in TTTS?

Answer 22

Becomes hypoxic because donor twin deoxygenates blood supply - stimulates kidneys to increase erythropoeitin EPO -> stimulation of bone marrow to increase RBC -> polycythaemia

Question 23

WHy is the recipient hypoxic in TTTS?

Answer 23

Deoxygenated blood from donor is coming to recipient

Question 24

Why does recipient baby have increased risk of stroke

Answer 24

Polycythaemia - viscosity increased

Question 25

What is selective reduction

Answer 25

Killing one of the babies so the other survives

Question 26

How does selective reduction happen

Answer 26

Clamp cord of one
Inject potassium chloride

Question 27

When is selective reduction best to be done

Answer 27

16 weeks

Question 28

How do you choose the baby that survives

Answer 28

Cardiac function, brain blood flow etc - doppler blood flow

Question 29

What is twin anaemia polycythaemia sequence

Answer 29

One twin becomes anaemic whilst the other develops polycythaemia (raised haemoglobin).
Less acute than TTTS

Question 30

What do women with multiple pregnancy require additional monitoring for?

Answer 30

Anaemia

Question 31

How do you monitor for anaemia in multiplepregnacy

Answer 31

FBC at booking clinic, 20 weeks gestation, 28 weeks gestation

Question 32

why are additional US scans are required in multiple pregnancy

Answer 32

to monitor for foetal growth restriction, unequal growth and twin twin transfusion syndrome

Question 33

What additional scans are done in multiple pregnancies - mono vs dichroionic

Answer 33

Monochorionic - 2 weekly scans from 16 weeks
Dichorionic - 4 weekly scans from 20 weeks

Question 34

When is planned birth offered for uncomplicated monochorionic monoamniotic twins

Answer 34

32 and 33+6 weeks

Question 35

When is planned birth offered for monochorionic diamniotic twins

Answer 35

36 adn 36+6 weeks

Question 36

When is planned birth offered for uncomplicated dichorionic diamniotic twins

Answer 36

37 and 37+6 weeks

Question 37

When is planned birth for triplets

Answer 37

35+.6 weeks

Question 38

Why are corticosteroids given to multiple pregnancies before delivery

Answer 38

Help mature the lungs

Question 39

Which twins reuqire a C sections

Answer 39

Monoamniotic twins
Between 32 and 32+6 weeks

Question 40

When is vaginal delivery possible with diamniotic twins?

Answer 40

Cephalic presentation in first baby
C section may be necessary after successful delivery of the first

Question 41

When is elective C section advised for diamniotic twins

Answer 41

Presenting twin is not cephalic

Question 42

Whem cam delier second twin vaginally

Answer 42

When out 30 mins after first
Uterus contracts after first twin born and can cut off supply to second baby