Baylor University Medical Center Proceedings April 2014, Volume 27, Number 2 | Page 70

Table. Previously reported cases of nuchal cord entanglement Reference number First author Year of publication Number of cases Study design Frequency Study outcome 1 Lipitz S 1993 1016 newborns Retrospective + prospective 8% No effect on term birth weight 2 Larson JD 1995 326 newborns Retrospective 4% No effect on neonatal outcome. Increased risk of abnormal fetal heart rate pattern, operative vaginal delivery 3 Larson JD 1997 4029 newborns Retrospective 29% 4 Singh V 2003 1 intrauterine fetal death (IUFD) Prospective 5 Ghi T 2007 5 newborns Prospective 3% 6 Tepper R 2009 64 fetuses Prospective 43% 7 Gambhir PS 2011 3 cord entanglements Case report — Died (3), one due to nuchal cord 8 Dodds M 2012 3 nuchal cord entanglements Case report — Died (1) generally support that nuchal cord is a common finding in fetal life, with decreasing rates in the newborn (1, 2, 5, 6). However, rather than showing decreasing rates, one study showed that nuchal cord rates increased linearly from 6% in the 20th gestational week to 29% in the 42nd gestational week, regardless of whether the entanglement involved a single loop or multiple loops (3). The presence of nuchal cord seems to have no effect on the outcome of pregnancy in terms of birth weight, rate of stillbirth, or rate of vaginal delivery after induction (1–3, 5). Compared to no entanglement or only one cord entanglement, two or more cord entanglements have been associated with an abnormal fetal heart rate pattern, requiring more low or midforceps application with a lower 1-minute Apgar score and an umbilical artery pH ≤ 7.10 without any adverse neonatal outcome (2). Umbilical cord abnormalities, mainly umbilical cord constriction and coiling, have been shown to be related to 11% of intrauterine fetal deaths within 16 gestational weeks (4). Fetal demise due to nuchal cord entanglement has been reported to occur in the first or second trimester in two case reports (7, 8). A decreasing incidence of cord entanglement around the neck seems to be a normal phenomenon during fetal uterine development, but rare instances result in fetal demise. An autopsy study of 139 mostly second-trimester fetuses that died due to umbilical cord stricture and overcoiling revealed the absence of Wharton’s jelly as an intrinsic cord pathology (9). Likewise, a not-yet-clarified intrinsic umbilical cord anomaly associated with the physical compression of entanglement may 144 8% No effect on stillbirth rate Cord constriction, coiling, hemorrhage, thrombosis, amniotic bands as frequent causes of IUFD No effect on rate of vaginal delivery after induction A 63% rate of any cord entanglement in early fetal life explain why some rare cases of nuchal cord end in fetal demise. To date, nuchal cords have been shown to have significantly lower vascular coiling than ones without nuchal entanglement (10). The relevance of this finding in terms of fetal demise is not yet known. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. Lipitz S, Seidman DS, Gale R, Stevenson DK, Alcalay M, Menczer J, Barkai G. Is fetal growth affected by cord entanglement? J Perinatol 1993;13(5):385–388. Larson JD, Rayburn WF, Crosby S, Thurnau GR. Multiple nuchal cord entanglements and intrapartum complications. Am J Obstet Gynecol 1995;173(4):1228–1231. Larson JD, Rayburn WF, Harlan VL. Nuchal cord entanglements and gestational age. Am J Perinatol 1997;14(9):555–557. Singh V, Khanum S, Singh M. Umbilical cord lesions in early intrauterine fetal demise. Arch Pathol Lab Med 2003;127(7):850–853. Ghi T, D’Emidio L, Morandi R, Casadio P, Pilu G, Pelusi G. Nuchal cord entanglement and outcome of labour induction. J Prenat Med 2007;1(4):57–60. Tepper R, Kidron D, Aviram R, Markovitch O, Hershkovitz R. High incidence of cord entanglement during early pregnancy detected by three-dimensional sonography. Am J Perinatol 2009;26(5):379–382. Gambhir PS, Gupte S, Kamat AD, Patankar A, Kulkarni VD, Phadke MA. Chronic umbilical cord entanglements causing intrauterine fetal demise in the second trimester. Pediatr Dev Pathol 2011;14(3):252–254. Dodds M, Windrim R, Kingdom J. Complex umbilical cord entanglement. J Matern Fetal Neonatal Med 2012;25(9):1827–1829. Peng HQ, Levitin-Smith M, Rochelson B, Kahn E. Umbilica l cord stricture and overcoiling are common causes of fetal demise. Pediatr Dev Pathol 2006;9(1):14–19. Strong TH Jr, Manriquez-Gilpin MP, Gilpin BG. Umbilical vascular coiling and nuchal entanglement. J Matern Fetal Med 1996;5(6):359–361. Baylor University Medical Center Proceedings Volume 27, Number 2