RESUMEN
La vasa previa es una situación que se produce cuando vasos fetales intramembranosos aberrantes, procedentes de la placenta o del cordón umbilical, atraviesan el orificio cervical interno y se sitúan por delante de la presentación fetal. Su incidencia es de 1/2.000-1/3.000 embarazos, y la mortalidad perinatal asociada es del 52-66%, aproximadamente. La reducción de esta elevada mortalidad se basa en su diagnóstico prenatal. Exponemos a continuación el caso clínico de una gestante, con controles obstétricos correctos, que acude a urgencias a las 34,5 semanas por rotura prematura de membranas, objetivándose un líquido amniótico hemático y bradicardia fetal severa, por lo que se realiza una cesárea urgente, naciendo una niña con anemia severa, que ingresa en la unidad de neonatología, presentando buena evolución posterior. Presentamos también una revisión de la literatura de los años 1980 al 2008, a través de Medline, usando las palabras «vasa previa» (AU)
Vasa previa is a condition in which the intramembranous fetal blood vessels within the placenta or umbilical cord cross the internal os and become trapped between the fetus and the opening of the birth canal. The incidence of this entity varies from 1/2000 to 1/3000 pregnancies and the associated perinatal mortality rate has been reported to be as high as 52-66%. Reduction of this high perinatal mortality depends on prenatal diagnosis. We report the case of a pregnant woman with no abnormalities in antenatal visits who presented to the emergency service at 34.5 weeks of pregnancy due to premature rupture of membranes, at which time blood-stained amniotic fluid and severe fetal bradycardia were noted. An emergency cesarean section was performed. A female neonate was delivered with severe anemia. The neonate was admitted into the neonatology unit and subsequent outcome was favorable. We also provide a review of the literature published between 1980 and 2008 using Medline, with the key words "vasa previa" (AU)