Maternal Risk Factors for Abnormal Vascular Coiling of the Umbilical Cord

Abstract

The objective of this paper is to identify maternal risk factors for abnormal vascular coiling of the umbilical cord. The umbilical cords of 657 neonates were examined and the coiling index determined by dividing the total number of complete vascular coils by the length of the cord in cm. Obstetrical history, delivery data, and neonatal outcome were also evaluated. The frequency distribution of umbilical coiling index was normal (10 th and 90th percentile and mean +/- SD = 0.17, 0.37, and 0.26 +/- 0.09 coils/cm, respectively). Maternal risk factors for abnormal vascular coiling were extremes of age for hyper-coiling, obesity, gestational diabetes mellitus, and preeclampsia for non-coiling. Hyper-coiled and non-coiled cords were significantly associated with adverse perinatal outcome (p < 0.001) and cesarean delivery (p < 0.0001). Neonates whose mothers are old or young, obese, diabetic, or have preeclampsia are likely to have hyper-coiled or non-coiled umbilical blood vessels.

Ultrasound Assessment of Umbilical Cord Morphology in the First Trimester: A Feasibility Study

“…In view of the absence of concordance in monozygotic twins, the helical nature of the cord is possibly controlled by factors which may be partly genetic and partly environmental. For example, maternal diabetes, obesity and hypertension are associated with non-coiled cords [19,20]. …”

Sonographic assessment of the umbilical cord

“…[40][41][42][43] The latter number represent umbilical coiling quantified via umbilical coiling index (UCI). 44 The UCI is calculated by dividing the total number of coils by the total length of the cord immediately after delivery. 42 The majority of the published studies define hypocoiled (undercoiled) or hypercoiled (overcoiled) umbilical cords as below the 10th and above the 90th percentile, respectively.…”

“…42 The majority of the published studies define hypocoiled (undercoiled) or hypercoiled (overcoiled) umbilical cords as below the 10th and above the 90th percentile, respectively. 41,43,44 In one of the largest studies of 1329 umbilical cords, a total of 13% hypocoiled and 21% of hypercoiled umbilical cords were found. 40 The presence of hypo-and hypercoiled cords was associated with fetal demise (21%, 37%, respectively), fetal intolerance of labor (15%, 14%, respectively), and intrauterine growth restriction (29% and 10% respectively).…”

“…40 In an attempt to prognosticate adverse fetal outcomes, an ultrasound evaluation of the umbilical cord coiling demonstrated a significant correlation between antenatal UCI (aUCI) and postnatal UCI measurements, but these studies were limited to the third trimester or the immediate postpartum period. [43][44][45] However, an attempt to establish the correlation between aUCI obtained in the second trimester and UCI at delivery demonstrated less compelling results with a sensitivity of 78.9% and 25.4% to predict hypo-and hypercoiled umbilical cords, respectively. 46 Discordance between aUCI and UCI may be attributed to the presence of "mixed" coiling patterns or possibly to the evolution of UCI at latter gestation.…”

“…48 It is possible that the small number of subjects in this study 33 precluded observation of adverse pregnancy outcomes in those patients with abnormal umbilical cord coiling that was reported elsewhere. 39,[42][43][44] In regard of neonatal Apgars' scores at birth, a higher number of low scores (< 6), though not statistically significant, in association with hypercoiled umbilical cords were reported. 42,47 In majority of the umbilical cords a twisting of arteries over umbilical vein is observed.…”