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Nuchal cords

Leonhard Schaffer, MD
Roland Zimmermann, MD
Section Editors
Susan M Ramin, MD
Deborah Levine, MD
Deputy Editor
Vanessa A Barss, MD, FACOG


A loop of umbilical cord around the fetal neck (nuchal cord) is a common finding at delivery. Although available data are of low quality, the bulk of evidence suggests that nuchal cords are not associated with a statistically significant increase in the rate of any clinically important adverse fetal/neonatal event. In case reports and small case series, however, nuchal cords have been associated with adverse outcomes [1-3].


The term nuchal cord describes an umbilical cord that passes 360 degrees around the fetal neck. Nuchal cords can be classified as [4]:

Type A – A nuchal loop 360 degrees around the fetal neck where the placental end crosses over the umbilical end, entangling the neck in an unlocked pattern that can undo itself.

Type B – A nuchal loop 360 degrees around the fetal neck where the placental end crosses under the umbilical end, entangling the neck in a locked pattern that cannot undo itself. This pattern can form a true knot when it passes down over the fetal body.

Nuchal cords can occur as single or multiple entanglements around the fetal neck. They may be loose or mildly to severely constricting. Disruption of the smooth contour of the fetal neck compressing the skin in that area, referred to as the "divot sign" [5], has been used to define tight nuchal cords [6].


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Literature review current through: Mar 2016. | This topic last updated: Apr 20, 2015.
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  1. Nelson KB, Grether JK. Potentially asphyxiating conditions and spastic cerebral palsy in infants of normal birth weight. Am J Obstet Gynecol 1998; 179:507.
  2. Verdel MJ, Exalto N. Tight nuchal coiling of the umbilical cord causing fetal death. J Clin Ultrasound 1994; 22:64.
  3. Dhar KK, Ray SN, Dhall GI. Significance of nuchal cord. J Indian Med Assoc 1995; 93:451.
  4. Collins JH. Nuchal cord type A and type B. Am J Obstet Gynecol 1997; 177:94.
  5. Ranzini AC, Walters CA, Vintzileos AM. Ultrasound diagnosis of nuchal cord: the gray-scale divot sign. Obstet Gynecol 1999; 93:854.
  6. Pilu G, Falco P, Guazzarini M, et al. Sonographic demonstration of nuchal cord and abnormal umbilical artery waveform heralding fetal distress. Ultrasound Obstet Gynecol 1998; 12:125.
  7. Sherer DM, Abramowicz JS, Hearn-Stebbins B, Woods JR Jr. Sonographic verification of a nuchal cord following a vibratory acoustic stimulation-induced severe variable fetal heart rate deceleration with expedient abdominal delivery. Am J Perinatol 1991; 8:345.
  8. Sheiner E, Abramowicz JS, Levy A, et al. Nuchal cord is not associated with adverse perinatal outcome. Arch Gynecol Obstet 2006; 274:81.
  9. Schäffer L, Burkhardt T, Zimmermann R, Kurmanavicius J. Nuchal cords in term and postterm deliveries--do we need to know? Obstet Gynecol 2005; 106:23.
  10. Larson JD, Rayburn WF, Crosby S, Thurnau GR. Multiple nuchal cord entanglements and intrapartum complications. Am J Obstet Gynecol 1995; 173:1228.
  11. Larson JD, Rayburn WF, Harlan VL. Nuchal cord entanglements and gestational age. Am J Perinatol 1997; 14:555.
  12. Tepper R, Kidron D, Aviram R, et al. High incidence of cord entanglement during early pregnancy detected by three-dimensional sonography. Am J Perinatol 2009; 26:379.
  13. Sørnes T. Umbilical cord encirclements and fetal growth restriction. Obstet Gynecol 1995; 86:725.
  14. Mastrobattista JM, Hollier LM, Yeomans ER, et al. Effects of nuchal cord on birthweight and immediate neonatal outcomes. Am J Perinatol 2005; 22:83.
  15. EASTMAN NJ. Coiling of the umbilical cord around the foetal neck. J Obstet Gynaecol Br Emp 1957; 64:227.
  16. Lal N, Deka D, Mittal S. Does the nuchal cord persist? An ultrasound and color-Doppler-based prospective study. J Obstet Gynaecol Res 2008; 34:314.
  17. Clapp JF 3rd, Stepanchak W, Hashimoto K, et al. The natural history of antenatal nuchal cords. Am J Obstet Gynecol 2003; 189:488.
  18. Sherer DM, Manning FA. Prenatal ultrasonographic diagnosis of nuchal cord(s): disregard, inform, monitor or intervene? Ultrasound Obstet Gynecol 1999; 14:1.
  19. AIUM Practice Guideline for the Performance of Obstetric Ultrasound Examinations. http://www.aium.org/resources/guidelines/obstetric.pdf (Accessed on March 07, 2016).
  20. Qin Y, Wang CC, Lau TK, Rogers MS. Color ultrasonography: a useful technique in the identification of nuchal cord during labor. Ultrasound Obstet Gynecol 2000; 15:413.
  21. Hanaoka U, Yanagihara T, Tanaka H, Hata T. Comparison of three-dimensional, two-dimensional and color Doppler ultrasound in predicting the presence of a nuchal cord at birth. Ultrasound Obstet Gynecol 2002; 19:471.
  22. Jauniaux E, Mawissa C, Peellaerts C, Rodesch F. Nuchal cord in normal third-trimester pregnancy: a color Doppler imaging study. Ultrasound Obstet Gynecol 1992; 2:417.
  23. Funk A, Heyl W, Rother R, et al. [Subpartal diagnosis of umbilical cord encirclement using color-coded Doppler ultrasonography and correlation with cardiotocographic changes during labor]. Geburtshilfe Frauenheilkd 1995; 55:623.
  24. Peregrine E, O'Brien P, Jauniaux E. Ultrasound detection of nuchal cord prior to labor induction and the risk of Cesarean section. Ultrasound Obstet Gynecol 2005; 25:160.
  25. Carey JC, Rayburn WF. Nuchal cord encirclements and risk of stillbirth. Int J Gynaecol Obstet 2000; 69:173.
  26. Jauniaux E, Ramsay B, Peellaerts C, Scholler Y. Perinatal features of pregnancies complicated by nuchal cord. Am J Perinatol 1995; 12:255.
  27. Sherer DM, Manning FA. Prenatal ultrasonographic diagnosis of conditions associated with potential umbilical cord compression. Am J Perinatol 1999; 16:445.
  28. Wang G, Bove KE, Stanek J. Pathological evidence of prolonged umbilical cord encirclement as a cause of fetal death. Am J Perinatol 1998; 15:585.
  29. Parast MM, Crum CP, Boyd TK. Placental histologic criteria for umbilical blood flow restriction in unexplained stillbirth. Hum Pathol 2008; 39:948.
  30. Tantbirojn P, Saleemuddin A, Sirois K, et al. Gross abnormalities of the umbilical cord: related placental histology and clinical significance. Placenta 2009; 30:1083.
  31. Ogueh O, Al-Tarkait A, Vallerand D, et al. Obstetrical factors related to nuchal cord. Acta Obstet Gynecol Scand 2006; 85:810.
  32. Osak R, Webster KM, Bocking AD, et al. Nuchal cord evident at birth impacts on fetal size relative to that of the placenta. Early Hum Dev 1997; 49:193.
  33. Lipitz S, Seidman DS, Gale R, et al. Is fetal growth affected by cord entanglement? J Perinatol 1993; 13:385.
  34. Carey JC, Rayburn WF. Nuchal cord encirclements and birth weight. J Reprod Med 2003; 48:460.
  35. Sherer DM, Sokolovski M, Dalloul M, et al. Is fetal cerebral vascular resistance affected by the presence of nuchal cord(s) in the third trimester of pregnancy? Ultrasound Obstet Gynecol 2005; 25:454.
  36. Aksoy U. Prenatal color Doppler sonographic evaluation of nuchal encirclement by the umbilical cord. J Clin Ultrasound 2003; 31:473.
  37. Assimakopoulos E, Zafrakas M, Garmiris P, et al. Nuchal cord detected by ultrasound at term is associated with mode of delivery and perinatal outcome. Eur J Obstet Gynecol Reprod Biol 2005; 123:188.
  38. Ghosh GS, Gudmundsson S. Nuchal cord in post-term pregnancy - relationship to suspected intrapartum fetal distress indicating operative intervention. J Perinat Med 2008; 36:142.
  39. Mendez-Bauer C, Troxell RM, Roberts JE, et al. A clinical test for diagnosing nuchal cords. J Reprod Med 1987; 32:924.
  40. Sherer DM, Menashe M, Sadovsky E. Severe fetal bradycardia caused by external vibratory acoustic stimulation. Am J Obstet Gynecol 1988; 159:334.
  41. Simmons JN, Rufleth P, Lewis PE. Identification of nuchal cords during nonstress testing. J Reprod Med 1985; 30:97.
  42. Miser WF. Outcome of infants born with nuchal cords. J Fam Pract 1992; 34:441.
  43. González-Quintero VH, Tolaymat L, Muller AC, et al. Outcomes of pregnancies with sonographically detected nuchal cords remote from delivery. J Ultrasound Med 2004; 23:43.
  44. D'Antona D, Aldrich CJ, Spencer JA, et al. Effect of nuchal cord on fetal cerebral haemodynamics and oxygenation measured by near infrared spectroscopy during labour. Eur J Obstet Gynecol Reprod Biol 1995; 59:205.
  45. Rhoades DA, Latza U, Mueller BA. Risk factors and outcomes associated with nuchal cord. A population-based study. J Reprod Med 1999; 44:39.
  46. Hankins GD, Snyder RR, Hauth JC, et al. Nuchal cords and neonatal outcome. Obstet Gynecol 1987; 70:687.
  47. Henry E, Andres RL, Christensen RD. Neonatal outcomes following a tight nuchal cord. J Perinatol 2013; 33:231.
  48. Clapp JF 3rd, Lopez B, Simonean S. Nuchal cord and neurodevelopmental performance at 1 year. J Soc Gynecol Investig 1999; 6:268.
  49. Spellacy WN, Gravem H, Fisch RO. The umbilical cord complications of true knots, nuchal coils, and cords around the body. Report from the collaborative study of cerebral palsy. Am J Obstet Gynecol 1966; 94:1136.
  50. Greenwood C, Impey L. The association of nuchal cord with cerebral palsy is influenced by recording bias. Early Hum Dev 2002; 68:15.
  51. Nielsen LF, Schendel D, Grove J, et al. Asphyxia-related risk factors and their timing in spastic cerebral palsy. BJOG 2008; 115:1518.
  52. Katz ME, Bass WT, White LE. Dural sinus ectasia after prolonged nuchal cord encirclement. J Ultrasound Med 1992; 11:289.
  53. Bäz E, Zikulnig L, Hackelöer BJ, Hecher K. Abnormal ductus venosus blood flow: a clue to umbilical cord complication. Ultrasound Obstet Gynecol 1999; 13:204.