Multiple Pregnancy Flashcards
What are the risk factors for multiple pregnancy
Previous multiple pregnancy Family History Increasing Parity Increasing maternal age Ethnicity – Nigerian and Japanese Assisted Reproduction – IUI, Clomiphene and IVF
What are the common symptoms women get with they are carrying twins
Hyperemesis Gravidarum
Uterus is larger for expected dates
Usually diagnosed on ultrasound at dating or nuchal translucency
What are the increased maternal risks of carrying twins
All multiple pregnancies are high risk because of an increased maternal risk of: • Pre-Eclampsia • Hyperemesis Gravidarum • Anaemia • GDM • Placenta Praevia • Antepartum and Post-partum haemorrhage • Operative delivery • Malpresentation • Foetal hypoxia in 2nd twin after first delivered • Cord prolapses
What are the increased foetal risks of being twins
Also increased foetal risk – especially in MC twins: • Miscarriage • Foetal anomalies • IUGR • Preterm delivery • PROM • Stillbirth • Disability • Cerebral palsy • Vanishing twin syndrome • Polyhydramnios
What are the different variations of twins
Dizygotic twins – two separate ova and so non identical twins. These twins are always dichorionic and diamniotic.
Monozygotic – one ova and so identical twins. Can be di or mono chorionic/amniotic. Most commonly MZ twins are MCDA.
How are women carrying twins managed during the antenatal period
Management
• Iron, Folate and Aspirin
• More frequent antenatal checks – USS every 2 weeks between 16-24 weeks then every 3 weeks until delivery
• Thorough plan for timing and place of delivery
• Establish presentation of leading twin by 34 weeks
• Induction by 38 weeks or Caesarean
• Close surveillance of MC twins
What are the main complications of Monochorionic, diamniotic twins
Twin to twin transfusion syndrome – one twin comes to rely on the others blood supply at the detriment of its twin. This can occur due to aberrant anastomoses in the placenta. Can be treated via laser ablation of placental anastomoses or selective feticide via cord compression.
• Donor twin: hypovolaemic, oligohydramnios, stuck to placenta wall and growth restriction.
• Recipient twin: hypervolemic and polycythaemia, large bladder and polyhydramnios, cardiac overload and failure, evidence of foetal hydrops (ascites, pleural and pericardial effusions).
How should selective intrauterine growth be managed in multiple pregnancies?
Which type of twins is it most complicated to selectively terminate in?
Selective intrauterine growth restriction – even without TTTS it is more common. Variable umbilical doppler signals indicates a high risk of sudden demise. If >28 weeks, then delivery is safest. Otherwise selective termination or laser ablation.
Termination is more complicated in MC twins due to the shared blood supply and so must occur via diathermy cord ablation.
What is twin reversed arterial perfusion?
Sever variant of twin to twin transfusion syndrome – one twin is very abnormal (pump twin) with no or a very rudimentary heart pump. As such this twin receives blood from the other (umbilical artery blood flow reversed)
How does the loss of a twin affect MC vs DC twins differently
Dichorionic - loss of one twin in 1st semester makes no difference to outcome of the other. However, loss in 2nd or 3rd trimester usually results in labour – 90% within 3 weeks
Monochorionic – death of one twin usually results in the loss of another (25% of the time).
How is Labour in multiple pregnancies managed
Second twin delivered is at highest risk of perinatal mortality.
Constant CTG monitoring – especially after 1st twin is delivered due to increased risks of foetal stress. Can monitor 1st twin via foetal scalp electrode and the 2nd abdominally. Should be delivered in theatres if vaginally. Mother will require lots of support.
1st twin delivered normally, then lie of 2nd determined (USS may be helpful) and stabilised by abdominal palpation while a VE is performed to assess the station of the presenting part. Once presenting part enters the pelvis then the membranes are broken and 2nd twin usually delivered within 20 mins of the first. If foetal distress occurs in second twin, then continue to forceps/ventouse. If inappropriate, then CS or can undergo breech extraction (gentle traction of feet.
Use oxytocin very carefully if contractions diminish after first twin.
Active 3rd phase = Syntometrine and Prophylactic oxytocin infusions due to increased risk of uterine atony.
