Multiple pregnancy Flashcards
(24 cards)
What is a multiple pregnancy?
A pregnancy with more than one fetus
What does monozygotic mean?
Identical twins (from a single zygote)
What does dizygotic mean?
Non identical twins (from two different zygotes)
What does monoamniotic mean?
Single amniotic sac
What does diamniotic mean?
Two separate amniotic sacs
What does monochorionic mean?
Share a single placenta
What does dichorionic mean?
2 separate placentas
What multiple pregnancy would have the best outcome?
Diamniotic, dichorionic pregnancies as they have their own nutrient supply each
When do you diagnose a multiple pregnancy?
Booking USS where you also measure the:
- gestational age
- number of placentas (chorionicity) and amniotic sacs (amnionicity)
- risk of Downs (combined test)
How can you tell if you have dichorionic diamniotic twins?
They will have a membrane between the twins with a lambda sign or twin peak sign
How can you tell if you have monochorionic diamniotic twins?
Membrane between the twins, with a T sign
How can you tell if you have monochorionic monoamniotic twins?
No membrane separating the twins
What are risks to the mother in a twin pregnancy?
Anaemia, Polyhydramnios - so hypertension, Spontaneous preterm birth, Instrumental delivery or C section, Postpartum haemorrhage
What are risks to fetuses in a twin pregnancy?
Miscarriage, Stillbirth, Fetal growth restriction, Prematurity, Twin-twin transfusion syndrome, Twin anaemia polycythaemia sequence
What is twin-twin transfusion syndrome?
Occurs when the fetuses share a placenta (monochorionic) where one fetus (the recipient) may receive the majority of blood from the placenta whilst the other one (donor) is starved of blood
Recipient- can become fluid overloaded with heart failure & polyhydramnois
Donor- growth restriction, anaemia & oligohydramnios
Where do you refer women with twin-twin transfusion syndrome?
Tertiary specialist fetal medicine centre where in severe cases laser treatment may be used to destroy the connection between the two blood supplies
What is twin anaemia polycythaemia sequence?
Similar to twin-twin transfusion syndrome but less acute where one twin becomes anaemic whilst the other develops polycythaemia (raised Hb)
What additional monitoring is done for twin pregnancies?
Anaemia with FBC done at booking clinic, 20 weeks & 28 weeks gestation
USS scans to monitor fetal growth: 2 weekly scans from 16 weeks for monochorionic twins & 4 weekly scans from 20 weeks for dichorionic twins
When is planned birth offered for uncomplicated monochorionic monoamniotic twins?
32 and 33 + 6 weeks
When is planned birth offered for uncomplicated monochorionic diamniotic twins?
36 and 36 + 6 weeks
When is planned birth offered for uncomplicated dichorionic diamniotic twins?
37 and 37 + 6 weeks
When is planned birth offered for triplets?
36 + 6 weeks
What type of birth is required in monoamniotic twins?
Elective C section between 32 and 33 weeks + 6 weeks
What type of birth is required in diamniotic twins?
Vaginal delivery is possible if first baby has cephalic presentation
C section may be required for second baby
Elective caesarean is advised when presenting twin is not cephalic
