Vasa praevia

Question 1

What is vasa praevia?

Answer 1

Vasa praevia is where the fetal vessels run close to the internal os putting the vessels at risk of rupture during rupture of membranes

The vessels are unprotected by the umbilical cord or placenta

Question 2

How does vasa praevia occur?

Answer 2

Velamentous umbilical cord - where the umbilical cord inserts into the chorioamniotic membranes and the fetal vessels run unprotected from there to the placenta

An accessory lobe of the placenta is connected by fetal vessels that run through the chorioamniotic membrane between the lobes

Question 3

What are the symptoms of vasa praevia?

Answer 3

Painless vaginal bleeding
Rupture of membranes
Fetal bradycardia
Antepartum haemorrhage

Question 4

What is type 1 vasa praevia?

Answer 4

Due to a velamentous umbilical cord

Question 5

What is type 2 vasa praevia?

Answer 5

Due to an accessory lobe of the placenta

Question 6

What are the risk factors for vasa praevia?

Answer 6

IVF pregnancy
Low lying placenta
Multiple pregnancy

Question 7

What are the differentials of vasa praevia?

Answer 7

Placenta praevia
Placental abruption

Question 8

What is the management of vasa praevia?

Answer 8

Corticosteroids given from 32 weeks gestation
Elective C section from 34-36 weeks (before rupture of membranes)

Question 9

What is the investigation of choice for the diagnosis of vasa praevia?

Answer 9

Transvaginal ultrasound