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Flashcards in Twin gestation Deck (22):
1

Causes of large for dates on examination

1. Wrong dates
2. Multiples
3. Molar
4. Uterine pathology
5. Polyhydramnios

2

Which has worse outcomes- monozygotic or dizygotic twins

Monozygotic
+pregnancy loss
Preterm delivery
Perinatal morbidity and mortality

3

Screening tests in twin pregnancy- accuracy differences

1. Fetal nuchal translucency performed with good accuracy, however the CFTS and biomarkers have less accurate risk stratification for twins.
2. Risks for down syndrome based on age also less accurate
3. Amniocentesis at 15-16 weeks, CVS can also be done->has +risk of spontaneous abortion
4. 18 week morphology scan

4

Information to provide for early pregnancy

1. Generally everything that happens in single pregnancy is more pronounced in twins
2. Consider stopping work at 28-30 weeks
3. If at 8 weeks 2 fetal hearts visible, likely to continue, miscarriage unlikely at that stage
4. Vaginal birth good possibility, although increased risk of C section in some.
5. Morning sickness should improve after 12 weeks. Eat small regular meals
6. Take iron and folate

5

Finishing the initial consult

1. Order normal pregnancy investigations
2. Information about support groups
3. Considerations for ongoing family planning
4. Review when results are back
5. Referral to hospital/midwife care- whichever is decided

6

Multiple gestation complications->mneumonic

The Ps of Multiple Gestation
Complications
Increased rates of:
Puking
Pallor (anemia)
Preeclampsia/PIH
Pressure (compressive symptoms)
PTL/PROM/PPROM
Polyhydramnios
Placenta previa/abruptio
PPH/APH
Prolonged labour
Cord Prolapse
Prematurity
Mal Presentation
Perinatal morbidity and mortality
Parental distress
Postpartum depression

7

Maternal complications

Hyperemesis gravidarum
GDM
Gestational HTN
Anemia
++Physiological stress
Compressive
C/S

8

Utero-placental complications

PROM/PTL
PolyH
PP
PL Abruption
PPH (atony)
Umbilical cord prolapse
Cord anomalies

9

Fetal complications

Prematurity
IUGR
Malpresentation
Congenital anomalies
TTT
Increased perinatal morbidity/mortality
Twin interlocking (breech + vertex)
Single fetal demise

10

Increased antenatal screening

USS every 2-3 weeks from 28 weeks to assess growth, may be further ++ if MCDA, MCMA

11

Vaginal vs C/S

Can attempt vaginal delivery if first twin is vertex, however often second twin will need to be delivered as C/S

12

Types of twin

Dichorionic, diamniotic
Dichorionic, monoamniotic
Monochorionic, diamniotic
Monochorionic, monoamniotic

13

Risk factors for dizygotic

Drugs
Race
Advanced maternal age
Parity
"Fraternal"

14

Frequency of maternal twins, monozygotic

Occurs in 1 in 250

15

Timing of divisions in monozygotic->amnionicity and chorionicity

1. Division of the ovum between days 0 and 3: Dichorionic, diamniotic monozygotic twins.
2. Division between 4 and 8 days: Monochorionic, diamniotic monozygotic twins
3. Division between 9 and 12 days: Monochorionic, monoamniotic monozygotic twins.
4. Division after 13 days: Conjoined twins.

16

Preferred first trimester screening marker

Nuchal translucency

17

What is twin-twin transfusion

Complication of monochorionic multifetal gestation in blood/IV volume shunted from one twin to another

18

Complications of TTT

Single fetal demise
One twin develops complication due to underperfusion, the other due to overperfusion

19

Etiology of TTT

Arterial blood from one passes through placenta to vein of the other

20

Clinical features of TTT

1. Donor twin: IUGR, hypovolemia, hypotension, anemia, oligohydramnios
2. Recipient: hypervolemia, HTN, CHF, polycythemia, edema, polyH, kernicterus in neonatal period

21

Ix in TTT

USS detection
Doppler flow analysis

22

Management of TTT

1. Therapeutic serial amniocentesis to decompress polyH of recipient and decrease pressure
2. IU blood transfusion to donor if necessary
3. Laparoscopic occlusion of placental vessels