T2 L15 Multiple pregnancy Flashcards
Describe the incidence of twin pregnancies across the world
2-7 per 1000 in far east
9-20 per 1000 in Europe
20-45 per 1000 in Nigeria
Why is the incidence of twin pregnancies rising?
Due to increasing maternal age and IVF
Why did the incidence of triplets decrease after 2002?
Law was introduced so only 1 embryo could be implanted during IVF
What is super ovulation?
More than 1 egg is released per menstrual cycle and all are then fertilised
What are the risk factors for super ovulation?
Ethnicity Increasing maternal age Increasing parity Family history Fertility treatment
What is the definition of monozygous?
1 egg
Twins are identical
1/3 of all twin pregnancies
What is the definition of dizygous?
2 eggs
Non identical
2/3 of twin pregnancies
Definition of dichorionic?
Each twin has its own chorionic sac and separate circulation
Must be diamniotic
How many monozygous twins are dichorionic?
1 in 3 monozygous twins
Definition of monochorionic?
Have vascularly joined placentae
How many monozygous twins are monochorionic?
2 in 3 monozygous twins
How are twin pregnancy diagnosed?
Uterine size
Diagnosed at delivery
Ultrasound
How many twin pregnancies are diagnosed at delivery?
50%
What is worse in multiple pregnancies?
Symptoms of pregnancy Anaemia Hypertension Intrauterine growth restriction Pre-term labour Delivery problems Perinatal mortality
Why are you likely to have an earlier due date with multiple pregnancies?
Going overdue increases the risk of stillbirth and the risks are already higher so the pregnancy is delivered earlier
Definition of stillbirth
Death after 24 weeks
Definition of early neonatal death
Death in first 7 days
Definition of neonatal death
Death in first 28 days
Definition of perinatal death
Combined numbers of stillbirth and early neonatal deaths
Definition of infant death
Death within 1st year
What is the first trimester management for a twin pregnancy?
Discuss screening for chromosomal anomalies
Determine chorionicity
Discuss foetal reduction if triplets or more
What is the management in the second trimester for a twin pregnancy?
Detection of foetal abnormality
Serial scans for growth for all
Serial scans for TTTS
Maternal complications
How often are dichorionic given scans?
Monthly from 24 weeks to check for growth restriction
How often are serial scans for TTTS done for monochorionic twins?
Fortnightly scans between 16-24 weeks and then monthly scans after this
When does twin to twin transfusion occur?
Occurs when identical twins share a placenta
Describe twin to twin transfusions
Unbalanced placental vascular anastomoses so blood flows unevenly.
Donor twin has decreased blood volume which restricts twin’s growth
Retrieving twin has increased blood volume which can cause heart failure
What is the management for twin to twin transfusion?
Treat with laser treatment or amnio-reduction
Early delivery by caesarean
What is the management for a twin pregnancy in the third trimester?
Scanning as in 2nd trimester
Monitor blood pressure
Pre-term labour
Delivery planning
Describe delivery planning for a twin pregnancy
37-38 weeks for dichorionic twins (vaginal or caesarean)
Presentation of twin
36-37 weeks for monochorionic twins (all by caesarean)
Pregnancy complications
Why are triplets always delivered by caesarean?
It is too difficult to monitor them for a vaginal delivery
What factors need to be managed during labour of twins?
Monitor both twins
Problems delivering twin II
Risk of postpartum bleeding
What should be considered if high order multiples?
Consider foetal reduction Determine chorionicity High risk of preterm labour Deliver preterm by caesarean Postpartum haemorrhage Difficult puerperium and after
