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].