The umbilical coiling index, a review of the literature

Our aim was to review the literature on umbilical cord coiling. Relevant articles in English published between 1966 and 2003 were retrieved by a Medline search and cross-referencing. The normal umbilical cord coiling index (UCI) is 0.17 (?± 0.009) spirals completed per cm. Abnormal cord coiling, i.e. UCI <?10th centile (?<?0.07) or >?90th centile (?>?0.30) is associated with adverse pregnancy outcome. Hypocoiling of the cord is...