Unruptured vasa previa with anomalous umbilical cord formation: a case of postpartum physician tachycardia.

Case A 22-year-old (gravida 3, para 1, aborta 1) woman was admitted to hospital at 39 weeks and 5 days of gestation with contractions and light blood show (ie, minor bleeding with mucus that is associated with cervical dilation). Shortly after arrival, her membranes ruptured spontaneously for a moderate amount of clear amniotic fluid. Vaginal examination revealed cervical dilation of 5 to 6 cm, cephalic presentation 2 cm above spines, and no untoward events. An initial fetal heart tracing showed normal results, and subsequent intermittent auscultation demonstrated no evidence of fetal distress. At full dilation the patient had a rapid second stage of labour, lasting only 11 minutes, and delivered a live baby girl weighing 3167 g. There was no evidence of abnormal bleeding. The baby’s Apgar scores were 6 at 1 minute and 8 at 5 minutes. Cord pH was 7.297 with a base excess of -2.5. The placenta was delivered 11 minutes after the baby, and the following tachycardia-inducing abnormality was noted. Five main vessels traversed the membranes, originating from various sites around the edge of the placenta. A total of 2 veins and 3 arteries left the marginal edge and traversed the sphere enclosed by the membranes. At the polar opposite side of the amniotic sphere, these vessels converged to form a normal umbilical cord with a configuration of 2 arteries and 1 vein. The membrane rupture occurred parallel to, and between, 2 of the vessels (1 artery, 1 vein). Fortunately none of the vessels was injured at the time of the rupture or in the course of delivery. The baby clinically showed no evidence of anemia and no hemoglobin was obtained. Blood transfusion was not required. The mother’s medical history included antibiotic treatment twice during pregnancy for identified infections (chlamydia at 9 weeks of gestation; abscessed tooth at 19 weeks). This was a spontaneous conception. Her previous pregnancy had ended with a spontaneous vaginal delivery, and there was no record of any placental problems or bleeding. Editor’s kEy points • Vasa previa is a serious and often fatal (to the fetus) obstetric emergency.