Recurrent antepartum compression of a single artery double nuchal cord necessitating emergency cesarean delivery

Fetuses with a single umbilical artery are considered at increased risk for chromosomal and structural abnormalities, and increased adverse perinatal outcome. A young nulliparous patient was followed with weekly nonstress testing due to well-controlled gestational diabetes, a single umbilical artery, and a double nuchal cord. At 31 weeks gestation, following the occurrence of a severe prolonged variable deceleration of the fetal heart rate the patient was hospitalized for close fetal surveillance with consideration that the deceleration may represent recurring intermittent compression of the single umbilical artery. Continuous fetal monitoring depicted recurrent severe variable decelerations of the fetal heart rate. Thirty-six hours after admission, prolonged fetal bradycardia to 60 bpm necessitated emergency cesarean delivery of a nonhypoxic nonacidotic fetus, which subsequently did well. This case suggests that fetuses with a single umbilical artery nuchal cord(s) may be at increased risk of significant umbilical cord compression.