High Risk Pregnancy
Multiple Pregnancy
Less than 2% - 15/1000 live birth
Types
Monozygotic (identical)
Dizygotic (non identical)
two separate fertilized eggs
Same or different gender - genetically like siblings
maternal age <20 .8% multiple
Rate rising due to assisteted conception and increase in maternal rate
Dichorionic diamniotic (DCDA)
two chorions/two amnions
may be dizygotic or monozygotic
Monochorionic diamniotic (MCDA)
one chorion / two amnions
monozygotic (2/3 MCDA - split 4-8days)
All dizygotic twins have DCDA
1/3 monozygotic twins have DCDA - splits 3-4days after fertilisation and before placental implantation
Monochorionic monoamniotic (MADA)
one chorion / one amnion 1% of cases (after 9 days)
Same Sex?
No
Yes
Dizygotic
How many placentas?
One - Monochorionic
Monozygotic
Two - dicharionic
Mono or Di - genetic testing to confirm
Twin to twin transfer (TTTS)