Multiple Births ✅ Flashcards
What is the incidence of twins?
1 in 89
What is the incidence of triplets?
1 in 4000
What has caused the increase in incidence of multiple births?
- Increased maternal age of childbearing
- Increased use of fertility enhancing techniques
What are the type of twins?
- Dizygotic
- Monozygotic
How many amnions do dizygotic twins have?
2
How many chorions do dizygotic twins have?
2
What is it called when twins have 2 chorions and 2 amnions?
Dichorionic-diamniotic
How many amnions to monozygotic twins have?
2
How many chorions do monozygotic twin have?
1 or 2
What is it called when twins have 1 chorion and 2 amnions?
Monochorionic-diamniotic
What are the main complications of multiple pregnancy?
- Preterm delivery
- Intra-uterine growth restriction
- Congenital abnormalities
- Twin twin transfusion syndrome
- Death of fetus
What is the median gestation of twin pregnancies?
37 weeks
What kind of twins are likely to need to be delivered preterm?
Monochorionic
In what kind of twins is intrauterine growth restriction particularly common?
Monochorionic
How much is the risk of congenital abnormality increased in twins?
2x in dichorionic (as there are 2 fetuses)
4x in monochorionic
What causes twin-twin transfusion syndrome?
Transfusion of blood across placental arteriovenous anastomoses in monochorionic twins
What are the features of the donor twin in twin twin transfusion syndrome?
- Hypovolaemic
- Growth restriction
- Oliguria
- Oligohydraminos
What are the features of the recipient twin in twin-twin transfusion syndrome?
- Hypervolaemic
- High output heart failure
- Polyuria
- Polyhydraminos
How is twin-twin transfusion syndrome managed?
Fetoscopic laser therapy to divide placental blood vessels
What might fetal death in one twin result in?
Preterm labour
What can fetal death of one twin lead to in monochorionic twins?
Blood loss from live to dead fetus, resulting in hyporolaemia, severe anaemia, neurological impairment, or death of the surviving twin
