7. Multi-Fetal Gestation and Malpresentation Flashcards
Describe epidemiology: Multi-Fetal Gestation (4)
- incidence of twins is 1/80 and triplets 1/6400 in North America
- 2/3 of twins are dizygotic (fraternal)
- risk factors for dizygotic twins: IVF, increased maternal age, newly discontinued OCP, and ethnicity (e.g. certain African regions)
- monozygous twinning occurs at a constant rate worldwide (1/250)
- determine zygosity by number of placentas, thickness of membranes, sex, and blood type
Name MATERNAL complications of multiple gestation (7)
- Hyperemesis gravidarum
- GDM
- Gestational
- HTN
- Anemia
- Increased physiological stress on all systems
- Increased compressive symptoms
- C/S
Name UTEROPLACENTAL complications of multiple gestation (7)
- Increased premature rupture of membranes (PROM)/preterm labour (PTL)
- Polyhydramnios
- Placenta previa
- Placental abruption
- postpartum hemorrhage PPH (uterine atony)
- Umbilical cord prolapse
- Cord anomalies (velamentous insertion, 2 vessel cord)
Name FETAL complications of multiple gestation (7)
- Prematurity
- intrauterine growth restriction (IUGR)
- Malpresentation Congenital anomalies
- Twin-twin transfusion
- Increased perinatal morbidity and mortality
- Twin interlocking (twin A breech, twin B vertex)
- Single fetal demise
Describe management of multiple gestation (4)
- U/S determination of chorionicity must be done within T1 (ideally 8-12 wk GA)
- increased antenatal surveillance
- serial U/S q3-4wk from 22 wk GA to assess growth (uncomplicated diamniotic dichorionic)
- increased frequency of U/S in monochorionic diamniotic and monochorionic monoamniotic twins
- Doppler flow studies weekly if discordant fetal growth (>30%)
- biophysical profile (BPP) as needed
- may attempt vaginal delivery if twin A presents as vertex, otherwise C/S (40-50% of all twin deliveries, 10% of cases have twin A delivered vaginally and twin B delivered by C/S)
- mode of delivery depends on fetal weights, GA, and presentation
Multiple Gestation has increased rates of what? (The Ps of Multiple Gestation Complications) (13)
- Puking
- Pallor (anemia)
- Preeclampsia/Pregnancy-Induced Hypertension (PIH)
- Pressure (compressive symptoms)
- PTL preterm labour/ premature rupture of membranes (PROM)/ preterm premature rupture of membranes (PPROM)
- Polyhydramnios
- Placenta previa/abruption
- postpartum hemorrhage (PPH)/ antepartum haemorrhage (APH)
- Prolonged labour Cord prolapse
- Prematurity Malpresentation
- Perinatal morbidity and mortality
- Parental distress
- Postpartum depression
Classify this twin pregnancy

Monoamniotic
Monochorionic
(forked cord)
Classify this twin pregnancy

- Monoamniotic
- Monochorionic
- time of cleavage: 9-12 d
Classify this twin pregnancy

- Monoamniotic
- Monochorionic
- (one cord)
Classify this twin pregnancy

- Diamniotic
- Dichorionic
- (fused)
- time of cleavage: 0-72 h
Classify this twin pregnancy

- Diamniotic
- Dichorionic
- (separated)
Classify this pregnancy

- Diamniotic
- Monochorionic
- time of cleage: 4-8 d
Define: Twin-Twin Transfusion Syndrome (1)
formation of placental intertwin vascular anastomoses causes arterial blood from donor twin to pass into veins of the recipient twin
Describe epidemiology: Twin-Twin Transfusion Syndrome (2)
- 10% of monochorionic twins
- concern if >30% discordance in estimated fetal weight
Describe clinical features of Twin-Twin Transfusion Syndrome: Donor twin (5)
- intrauterine growth restriction IUGR
- hypovolemia
- hypotension
- anemia
- oligohydramnios
Describe clinical features of Twin-Twin Transfusion Syndrome: Recipient twin (7)
- hypervolemia
- HTN
- congestive heart failure (CHF)
- polycythemia
- edema
- polyhydramnios
- kernicterus in neonatal period
Describe investigations: Twin-Twin Transfusion Syndrome (2)
detected by
- U/S screening
- Doppler flow analysis
Describe management: Twin-Twin Transfusion Syndrome (4)
- therapeutic serial amniocentesis to decompress polyhydramnios of recipient twin and decrease pressure in cavity and on placenta
- intrauterine blood transfusion to donor twin if necessary
- laparoscopic occlusion of placental vessels
- fetoscopic laser ablation of placental vascular anastomoses when indicated and if available
Define: Breech Presentation (4)
- fetal buttocks or lower extremity is the presenting part as determined on U/S
- complete (10%): hips and knees both flexed
- frank (60%): hips flexed, knees extended, buttocks present at cervix
- most common type of breech presentation
- most common breech presentation to be delivered vaginally
- incomplete (30%): both or one hip partially flexed and both or one knee present below the buttocks, feet or knees present first (footling breech, kneeling breech)

Describe epidemiology: Breech presentation (1)
- occurs in 3-4% of pregnancies at term (25% <28 wk)
Name MATERNAL risk factors: Breech presentation (4)
- pelvis (contracted)
- uterus (shape abnormalities, intrauterine tumours, fibroids, previous breech)
- pelvic tumours causing compression
- grand multiparity
Name PLACENTAL risk factors: Breech presentation (1)
- placenta previa
Name FETAL risk factors: Breech presentation (8)
- prematurity
- amniotic fluid (poly-/oligohydramnios)
- multiple gestation
- congenital malformations (found in 6% of breeches; 2-3% if in vertex presentations)
- abnormalities in fetal tone and movement
- aneuploidy
- hydrocephalus
- anencephalus
Describe management: Breech presentation (4)
- ECV (external cephalic version): repositioning of singleton fetus within uterus under U/S guidance
- pre-or early-labour U/S to assess type of breech presentation, fetal growth, estimated weight, placenta position, attitude of fetal head (flexed is preferable); if U/S unavailable, recommend C/S
- ECV and elective C/S should be presented as options with the risks and benefits outlined; obtain informed consent
- method for vaginal breech delivery
What’s the overall success rate: ECV (external cephalic version)
- of ~60%
Name criteras: ECV (external cephalic version) (5)
- >36 wk GA
- singleton
- unengaged presenting part
- reactive non-stress test NST
- not in labour
Name absolute contraindications: ECV (external cephalic version) (7)
- where C/S is required (placenta previa, previous classical C/S),
- previous myomectomy
- premature rupture of membranes PROM
- uteroplacental insufficiency
- nuchal cord
- non-reactive non-stress test (NST)
- multiple gestation
Name relative contraindications: ECV (external cephalic version) (4)
- mild/moderate oligohydramnios
- suspected intrauterine growth restriction (IUGR)
- HTN
- previous T3 bleed
Name risks: ECV (external cephalic version) (8)
- abruption
- cord compression
- cord accident
- rupture of membranes ROM
- labour
- fetal bradycardia requiring C/S (<1% risk)
- alloimmunization
- fetal death (1:5000)
Describe method: ECV (external cephalic version) (2)
- tocometry, followed by U/S guided transabdominal manipulation of fetus with constant fetal heart monitoring
- if patient Rh negative, give Rhogam® after the procedure
Name factors of better prognosis: ECV (external cephalic version) (5)
- if multiparous
- good fluid volume
- small baby
- skilled obstetrician
- posterior placenta
Describe: Method for vaginal breech delivery (4)
- encourage effective maternal pushing efforts
- at delivery of head (after feet), assistant must apply suprapubic pressure to flex and engage fetal head
- delivery can be spontaneous or assisted; avoid fetal traction
- apply fetal manipulation only after spontaneous delivery to level of umbilicus
Name contraindications to vaginal breech delivery (3)
- cord presentation
- clinically inadequate maternal pelvis
- fetal factors incompatible with vaginal delivery (e.g. hydrocephalus, macrosomia, fetal growth restriction)
When is C/S recommended for breech presentation? (3)
- the breech has not descended to the perineum in the second stage of labour after 2 h
- in the absence of active pushing
- or if vaginal delivery is not imminent after 1 h of active pushing
Describe prognosis: Breech presentation? (5)
regardless of route of delivery, breech infants have
- lower birth weights
- higher rates of perinatal mortality
- congenital anomalies
- abruption
- cord prolapse