Introduction
Vasa previa is defined as placental vessels supported only by membranes,
overlie the cervix, lie between the cervix and the presenting fetal
part[1]. The prevalence of vasa previa is
approximately 1 in 2500, but much higher among patients with low lying
placenta, in vitro fertilization(IVF), or abnormal placental morphology,
such as bipartite or succenturiate lobe placentas in the lower uterine
segment[2]. These previa vessels are vulnerable
not only to compression, which may lead to fetal anoxia, but also to
laceration, which can lead to acute fetal blood loss or
exsanguination[3]. That results in poor pregnancy
outcomes if not diagnosed prenatally[4].