Overcoiling of the Umbilical Cord

Abstract

1 m 4 2 i female infant was born at 35 weeks of gestation by cesarean ection, performed because of intrauterine growth restriction nd absent or reversed end-diastolic (ARED) flow in the mbilical artery. Birth weight was 1690 g (3rd percentile), ength was 41 cm ( 3rd percentile), and head circumference as 33.3 cm (75-90th percentile). Apgar scores were 8 and 9 t 1 and 5 minutes, respectively. The umbilical cord had 38 ounterclockwise complete coils (Figure), and the length was 1 cm. The umbilical cord is usually spiraled. A counterclockise spiral is more frequent than a clockwise spiral with a ratio f 7:1. The origin of umbilical cord coiling is unknown. ypotheses include fetal movements, active or passive torsion f the embryo, differential umbilical vascular growth rates, etal hemodynamic forces, and the arrangements of muscular bers in the umbilical arterial wall. The coiling of the umbilcal vessels develops as early as 28 days after conception and is resent in about 95% of fetuses by 7 weeks of conception. The elices may be seen by ultrasonographic examination as early igure. Umbilical cord with counterclockwise complete coils. (Available n color at www.jpeds.com.)