Twins

Question 1

What is zygosity

Answer 1

Monozygotic if embryo splits and creates identical twins

Dizygotic if 2 eggs are fertilised

Question 2

What is chorionicity

Answer 2

Number of placentae

Question 3

What is amniocentesity

Answer 3

Number of gestational sacs

Question 4

What is lambda sign on US

Answer 4

Roughly 4mm thickened membrane between 2 separate gestational sacs
Confirms diamniotic, dichorionic twins

Question 5

Complications of twins

Answer 5

1st trimester: anaemia, hyperemesis, miscarriage
2nd trimester: GDM, preeclampsia, prematurity, IUGR, APH, twin-twin transfusion
Term: PPH, c section, stillbirth, PND

Question 6

Antenatal requirements of twins

Answer 6

Specialist midwife care
Consultant care
USS every 4 weeks from 24/26 weeks
Iron tablets
Folic acid
Aspirin 75mg from 12 weeks 
Down syndrome screening 1st trimester only

Question 7

Delivery of twins

Answer 7

At 37 weeks

NVD if twin 1 cephalic, otherwise C section

Question 8

Antenatal requirements specifically for monochorionic twins

Answer 8

Screen for twin twin transfusion every 2 weeks from 16 weeks

Question 9

Management of twin twin transfusion

Answer 9

Ablation of connection with laser

As early as possible, need early detection for improved outcome

Question 10

Features of twins in twin twin transfusion

Answer 10

Recipient - large, cardiac overload

Donor - small, anaemia