Vasa praevia is said to occur when the foetal blood vessels
traverse the membranes over the cervix, below the presenting
part.1 There are two variants: type 1, which results
from velamentous insertion of the umbilical cord, and type
2, which occurs when foetal vessels run between the lobes of
a bilobed or succenturiate-lobed placenta.2 Its incidence is
approximately 1 in every 2500 pregnancies.3 Spontaneous or
artificial rupture of the membranes leads to a tearing of the
foetal blood vessels, frequently giving rise to rapid foetal
exsanguination3 and high perinatal mortality