Background: The rare entity of vasa previa occurs when fetal vessels lying between the amniotic and chorionic membranes cross the cervical os. This report presents a case that was associated with vessel compression and concomitant adverse effects on fetal hemodynamics.
Case: A 23-year-old nulliparous woman at 36 weeks' gestation developed persistent, progressive severe variable decelerations several hours after spontaneous rupture of the membranes, resulting in a decision to perform a cesarean. At delivery, fetal vessels were noted in the membranes near the cervical os, leading into a marginally inserted cord. The decelerations were attributed to compression of the unprotected umbilical arteries by the fetal head.
Conclusion: Vasa previa often results in fetal death and may be associated with fetal hemorrhage, but lack of bleeding does not exclude the existence of vasa previa. Altered fetal hemodynamics from varying degrees of vessel compression by the presenting part during labor may result in hypoxia and acidosis. A high index of suspicion is necessary to make the diagnosis and institute proper, timely management.