Multiple Pregnancies Flashcards
Why are twin pregnancies increasing?
Use of IVF
-insertion of multiple embryo
Ovarian hyperstimulation
Use of clomifene to increase fertility
What is zygosity?
Number of eggs fertilised
1 egg=monozygotic=identical
(one third are dichorionic)
2 eggs released=dizygotic=non-identical (two thirds of twins)
What is chorionicity?
Description of the number of chorion sac and placenta
-Early splitting leads to dichorionic pregnancy
Monochorion
- 1 chorion
- 1 placenta
Dichorion
- Seperate chorion
- Seperate placenta
- All dizygotic twins are dichorionic
Amnioticity
Describes the number of amniotic sacs in multiple pregnancy
Monoamniotic (MA)
- only one amniotic sac shared
- only with monozygotic twins
Diamniotic (DA)
-seperate amniotic sac
MCDA
monochorionic (this means identical)
diamniontic
joined placentae
this happens when the splitting occurs later
DCDA
2 parallel pregnancies
dichorionic
diamniotic
and seperate placentae
They can be mono or dizygotic twins
(monozygotic if it splits earlier)
MCMA
monochorionic
monoamniotic
joined placentae
if splits laterr
risk of chords tangling and blood supply cutting off
How is a multiple pregnancy diagnosed?
Uterine size
US
worldwide=on delivery
what does the lamda sign show?
dichorionic twins
What does t sign show
they are monochorionic twins
Complications associated with multiple pregnancies
Anaemia hypertension IUGR preterm labour (increase in fluid) delivery problems perinatal mortality
What is twin to twin transfusion syndrome in monochorionic twin pregnancies?
connections between the placental BV
usually there shouldnt a shunt and both babies should get equal
i.e one baby gets more blood
unbalanced placental vascular anastomosis
likely to lose both
TREATMENT- (laser or amnio-reduction)
laser the vessels connecting the 2 pregnancies
