Обвитие пуповиной

[Andru]

Здравствуйте уважаемые коллеги. У нас погиб ребёнок в родах. Самая вероятная причина обвитие пуповиной во втором периоде и острая гипоксия. Прошу помощи в изучении статистики по данной проблеме. Обратило на себя внимание скудное развитие Вартониева студня по этой теме вообще ничего не нашёл. Буду благодарен за ссылки и личный опыт.
Андрей Владимирович Алексеев.

[DrTatyana]

Histopathology of placental disorders
Author Drucilla J Roberts, MD Section Editors Charles J Lockwood, MD
Rochelle L Garcia, MD Deputy Editor Vanessa A Barss, MD
Disclosures
All topics are updated as new evidence becomes available and our peer review process is complete.
Literature review current through: Jun 2013. | This topic last updated: янв 28, 2013.

UMBILICAL CORD — The histopathologic findings in the cord can be grouped as congenital remnants, infections, meconium, and masses.

Congenital remnants — The end of the umbilical cord closest to the infant often contains residual developmental structures such as the allantoic and vitelline ducts and vitelline vessels [1]. None of these findings has clinical significance.

Infection — The most common intrauterine infection is bacterial ("acute") chorioamnionitis, which is an amniotic fluid infection caused by cervical/vaginal flora breaching the amniotic cavity. The inflammatory response to this infection can be of both maternal and fetal origin. As an example, the umbilical cord may harbor maternal inflammatory cells (primarily neutrophils) that have infiltrated from the decidua to the amniotic fluid. Alternatively, the fetus may respond to infectious stimuli with a fetal inflammatory neutrophilic response in which fetal inflammatory cells migrate from fetal vessels (including those of the umbilical cord) toward the infectious agent in the cord, membranes, or amniotic fluid [2].

Umbilical cord inflammation has many names, such as funisitis and vasculitis. Standardization of terminology has been proposed to clarify the source (maternal or fetal) of the inflammatory cells [3] due to a significant difference in the risk for development of neurologic compromise in the fetus [4]. Funisitis involving only the external surface of the cord and Wharton's jelly most likely originated from outside the fetus and is maternal in origin. The inflammatory cells seen migrating through the fetal vessels in the cord are evidence of a fetal response and are diagnostic of systemic fetal inflammatory response syndrome (picture 1) [5]. Funisitis is predictive of a lower median Bayley psychomotor developmental index, 94 versus 99 among infants without funisitis (OR 1.3, 95% CI 1.1-1.9) [6]. It may also be a risk factor for other adverse outcomes as inflammation of the umbilical cord may be a marker for vascular inflammation elsewhere in the fetus.

The umbilical cord is trophic for some specific infectious organisms including candida [5] and toxoplasmosis [5]. These organisms can also be observed in the areas of inflammation. Candidal infection is frequently associated with neutrophilic microabscesses on the external surface of the umbilical cord.

Meconium stained cord — Meconium pigment in the amniotic fluid will be picked up by macrophages in the placental membranes and umbilical cord and change the color and clarity of these structures. However, this is an uncommon finding compared to the frequency of meconium in amniotic fluid, suggesting that heavy or long duration of exposure to meconium is required to stain the membranes.

A high concentration of meconium present for more than 12 hours can damage the umbilical cord by causing apoptosis of smooth muscle cells [7]. The histologic findings are an orangeophilic (ie, orange appearing cytoplasm) apoptotic-like degeneration of the arteries (usually) in a characteristic pattern that spares the centrally facing myocytes. An inflammatory infiltrate is often present.

Meconium-induced umbilical cord vascular necrosis has been associated with postdates pregnancy, oligohydramnios, low cord pH, low Apgar scores, and significant neurodevelopmental delay in retrospective studies [7-10]. Fetal and neonatal morbidity is thought to be due to interruption of the normal blood flow in the cord causing intermittent or prolonged hypoxia in utero. There are no prospective studies to establish whether this finding should cause concern and early intervention postdelivery.

Masses — The most common mass of the umbilical cord is a hematoma that is present near the cord clamp (picture 4 and picture 5). This is a sequela of cord clamping and of no clinical significance since it is an iatrogenic postdelivery event.

The umbilical cord is also host to rare tumors including mature cystic teratomas [11-13], hemangiomas [14-16], angiomyxomas [17,18], and intestinal polyps (ie, polypoid intestinal masses that probably develop within the vitelline duct remnant) [19]. Any of these masses can cause fetal morbidity or death in utero, if large enough, due to compression/obstruction of the umbilical cord vessels.

Arterial and venous thrombosis — Intrauterine thrombosis of umbilical artery is rare and can be followed by poor fetal outcome, such as intrauterine growth restriction or fetal demise [20-23]. Remote arterial thromboses can result in the appearance of a single umbilical artery (two-vessel cord). As long as one patent artery remains, the outcome is not lethal, but an adverse outcome may result, as the thrombus can embolize to the placenta and result in loss of viable (functioning) parenchyma (see below).

Umbilical venous thrombosis, although rare, can be fatal if complete. Partial thrombosis can embolize to the fetus, and cause cerebral or renal infarcts. Venous thrombosis occurs alone in approximately 70 percent of cases, both venous and arterial thrombosis occur in approximately 20 percent of cases, and arterial thrombosis occurs alone in 10 percent of cases [24]. Possible causes of any umbilical thromboses include cord accidents (hypertwisting, knots, prolapse), fetal thrombophilia, peripheral cord insertion, meconium myonecrosis, and funisitis [22,25], although many remain unexplained. Venous thrombosis has been associated with maternal diabetes, acute chorioamnionitis, and meconium-induced umbilical vascular necrosis (although umbilical artery involvement is more common).
1.Jauniaux E, De Munter C, Vanesse M, et al. Embryonic remnants of the umbilical cord: morphologic and clinical aspects. Hum Pathol 1989; 20:458.
2.Yoon BH, Romero R, Park JS, et al. The relationship among inflammatory lesions of the umbilical cord (funisitis), umbilical cord plasma interleukin 6 concentration, amniotic fluid infection, and neonatal sepsis. Am J Obstet Gynecol 2000; 183:1124.
3.Redline RW, Faye-Petersen O, Heller D, et al. Amniotic infection syndrome: nosology and reproducibility of placental reaction patterns. Pediatr Dev Pathol 2003; 6:435.
4.Redline RW. Placental pathology and cerebral palsy. Clin Perinatol 2006; 33:503.
5.Qureshi F, Jacques SM, Bendon RW, et al. Candida funisitis: A clinicopathologic study of 32 cases. Pediatr Dev Pathol 1998; 1:118.
6.Mittendorf R, Montag AG, MacMillan W, et al. Components of the systemic fetal inflammatory response syndrome as predictors of impaired neurologic outcomes in children. Am J Obstet Gynecol 2003; 188:1438.
7.Altshuler G, Arizawa M, Molnar-Nadasdy G. Meconium-induced umbilical cord vascular necrosis and ulceration: a potential link between the placenta and poor pregnancy outcome. Obstet Gynecol 1992; 79:760.
8.Lewis SH, Gilbert-Barness E. The placenta and its significance in neonatal outcome. Adv Pediatr 1998; 45:223.
9.Naeye RL. Can meconium in the amniotic fluid injure the fetal brain? Obstet Gynecol 1995; 86:720.
10.Miller PW, Coen RW, Benirschke K. Dating the time interval from meconium passage to birth. Obstet Gynecol 1985; 66:459.
11.Kreczy A, Alge A, Menardi G, et al. Teratoma of the umbilical cord. Case report with review of the literature. Arch Pathol Lab Med 1994; 118:934.
12.Driscoll SG. Umbilical cord teratoma. Hum Pathol 1985; 16:1178.
13.Smith D, Majmudar B. Teratoma of the umbilical cord. Hum Pathol 1985; 16:190.
14.Ghidini A, Romero R, Eisen RN, et al. Umbilical cord hemangioma. Prenatal identification and review of the literature. J Ultrasound Med 1990; 9:297.
15.Kamitomo M, Sueyoshi K, Matsukita S, et al. Hemangioma of the umbilical cord: stenotic change of the umbilical vessels. Fetal Diagn Ther 1999; 14:328.
16.Søndergaard G. Hemangioma of the umbilical cord. Acta Obstet Gynecol Scand 1994; 73:434.
17.Carvounis EE, Dimmick JE, Wright VJ. Angiomyxoma of umbilical cord. Arch Pathol Lab Med 1978; 102:178.
18.Yavner DL, Redline RW. Angiomyxoma of the umbilical cord with massive cystic degeneration of Wharton's jelly. Arch Pathol Lab Med 1989; 113:935.
19.Lee MC, Aterman K. An intestinal polyp of the umbilical cord. Am J Dis Child 1968; 116:320.
20.Klaritsch P, Haeusler M, Karpf E, et al. Spontaneous intrauterine umbilical artery thrombosis leading to severe fetal growth restriction. Placenta 2008; 29:374.
21.Solano Sánchez SR, Baquera Heredia JJ, Reyes Cuervo H, Buen Abad EI. [Umbilical artery thrombosis. A report of a case and review of the literature]. Ginecol Obstet Mex 2005; 73:332.
22.Sato Y, Benirschke K. Umbilical arterial thrombosis with vascular wall necrosis: clinicopathologic findings of 11 cases. Placenta 2006; 27:715.
23.Afriat R, Bidat L, Fortier F, et al. [Prenatal diagnosis of spontaneous thrombosis of the umbilical artery during the third trimester of pregnancy. Two cases with surviving infants]. J Gynecol Obstet Biol Reprod (Paris) 1995; 24:411.
24.Heifetz SA. Thrombosis of the umbilical cord: analysis of 52 cases and literature review. Pediatr Pathol 1988; 8:37.
25.Ariel I, Anteby E, Hamani Y, Redline RW. Placental pathology in fetal thrombophilia. Hum Pathol 2004; 35:729.

[DrTatyana]

Gross examination of the placenta
Author Drucilla J Roberts, MD Section Editors Charles J Lockwood, MD
Rochelle L Garcia, MD Deputy Editor Vanessa A Barss, MD
Disclosures. All topics are updated as new evidence becomes available and our peer review process is complete.
Literature review current through: Jun 2013. | This topic last updated: янв 28, 2013.

UMBILICAL CORD — The umbilical cord is normally composed of two umbilical arteries and an umbilical vein supported by loose gelatinous tissue called Wharton's Jelly.

Appearance — The umbilical cord should have a smooth, white, opaque, shiny appearance with spiraling consisting of about three half spirals over a 5 cm length of cord. Abnormal coloring suggests infection, meconium, or the sequelae of fetal demise.

Nodules on the cord suggest abscesses and may be a sign of candidal infection.

Mild edema of the umbilical cord is common and of no clinical significance. Massive edema (resulting in regional or diffuse cord diameters of greater than 3 cm) can cause vascular compromise and is often associated with acute changes in the fetal heart rate pattern. Some pathologists have termed areas of massive cord edema "angiomyxoma" due to the histologic appearance [7,8].

A stricture may be artifactual or the result of torsion or amniotic bands. Strictures can be important findings, as they have been implicated in the etiology of fetal demise or compromise. They should be carefully described and sampled on both sides of the stricture and through the stricture.

Coiling — The umbilical cord has a characteristic twist or coil (Cord spirals normally 1 turn per 3 cm). Twisting is usually to the left (like a barber pole), but the direction of twist (left versus right) is not an important factor in pregnancy outcome [9,10]. Coiling of the umbilical cord is thought to protect it from compression, kinking, and torsion, thus preventing disruption of the blood supply to the fetus. Coiling may also facilitate umbilical venous blood flow [11]. The genesis of cord twist is unclear, but likely reflects fetal movement or differences in the growth rates of the fetal vessels [12,13].

Examination of the umbilical cord provides information about fetal growth and activity in utero. Cords with no coiling are associated with poor fetal growth and decreased activity, and may result from severe neural and musculoskeletal anomalies [14,15]. Several studies have reported an increased frequency of adverse pregnancy outcome, including congenital anomalies, growth restriction, fetal heart rate abnormalities, preterm birth, and intrauterine death in patients with an uncoiled umbilical cord [16-19]. Both hypocoiled and hypercoiled umbilical cords are associated with an increased frequency of small for gestational age neonates (15 to 16 percent versus 5 percent with normocoiled cords for both) and nonreassuring fetal heart rate patterns (22 to 29 percent versus 11 percent) [20,21].

Placental insertion — The umbilical cord normally inserts centrally or slightly eccentrically and directly into the placental disk. Fewer than 10 percent of insertions occur at the margin of the placenta (battledore placenta) (picture 5).

A velamentous cord insertion refers to a cord that inserts into the membranes rather than the placental disk. The velamentous vessels are surrounded only by fetal membranes, with no Wharton's jelly, thus they are prone to compression or disruption. Velamentous vessels can also occur between lobes of a bilobed placenta. Velamentous umbilical cord has been associated with several obstetrical complications, including fetal growth restriction, prematurity, congenital anomalies, and low Apgar score.

A furcate (forked) cord is a rare variation of the velamentous cord. The fetal vessels are also unsupported by Wharton's jelly, but they separate from each other and fan out to form a vascular "tent" just above the disk. Although the appearance is worrisome, furcate cords are rarely associated with an adverse pregnancy outcome.

Abnormalities of umbilical cord insertion are more common in pregnancies resulting from in vitro fertilization [22,23] and in multiple gestations. Abnormal cord insertions should be noted and histologic examination should be undertaken to look for thrombi and vascular anomalies, which are associated with these abnormalities [24].

Length — Cord length increases with advancing gestational age. The average length at term is 55 cm, with a wide normal range (35 to 70 cm) [14]. The length should be noted and compared with published standards (table 2). The length measurement should include the portion of cord on the infant after cord transection at delivery as well as the part remaining with the placenta, thus it is best determined in the delivery room. If the length of the cord attached to the infant is not provided to the pathologist, he/she cannot determine whether the total length of cord (placental portion plus infant portion) is shorter than normal and will not make the diagnosis of "short umbilical cord" (table 2). A "long umbilical cord" is diagnosed when more than 70 cm of cord is received at term [9,25,26].

The length of the umbilical cord can be of critical importance when evaluating a case of perinatal morbidity or mortality. Cord length is determined in part by hereditary factors, but also by the tension the fetus places on the cord when it moves. For this reason, short cords are associated with fetal inactivity related to fetal malformations, myopathic and neuropathic diseases, oligohydramnios, and some syndromes [15,27]. Long cords may be caused by a hyperactive fetus and have been associated with cord accidents, such as entanglement, knotting, and prolapse [14]. Long cords are also associated with placental lesions indicative of intrauterine hypoxia, as well as fetal death, fetal growth restriction, and long term adverse neurologic outcome [28]. In addition, the longer route that blood must travel to and from the fetal heart when the cord is very long may result in fetal heart failure.

[DrTatyana]

Продолжение

Knots — False knots are tortuousities of the umbilical vessels that form bulges (picture 6); they are not associated with any adverse outcome.

True knots occur in 1 percent of births and are generally single and loose (picture 7) [29]. However, tight (picture 8) or multiple true knots and knots associated with coiling or twisting of the cord increase the risk of intrauterine demise, particularly if the cord is long and during the second trimester when the fetus has a lot of room to move. The medical record should document the presence of a true knot, the tightness or laxity of the knot, the presence of unilateral edema of the cord relative to the knot, and whether there are thrombi in the vessels. A pathologist should obtain a section through the knot for histologic examination. The appropriate management of true knots identified by ultrasound examination antepartum is unclear [30].

Vessels — A single umbilical vein conducts blood from the placenta back to the fetus and is essential for fetal survival. The two umbilical arteries shunt blood from the fetus to the placenta. Their redundancy is evident, given that the presence of a single umbilical artery or hypoplastic second umbilical artery is not lethal.

The number of umbilical vessels are best counted by cutting the cord in a relatively uniform region (away from bulges of false knots) at least 5 cm from the placental insertion since the two arteries sometimes fuse near the insertion [24]. Two vessel cords should be documented in the medical record and confirmed by histological examination.

Vessels that are expanded and contain laminated thrombi are abnormal and should be investigated. Possible etiologies include cord compression from a true knot, cord prolapse, or head compression; marginal or membranous cord insertion; a fetal hypercoagulable state (eg, sepsis, hereditary thrombophilia); and maternal diabetes mellitus [31].

Hematomas due to trauma at delivery are commonly observed near the cord clamp and at the insertion of the cord into the placental disk. True spontaneous hematomas of the umbilical cord do occur, but are rare and often lethal.

True hemangiomas of the umbilical cord are also rare, and associated with fetal death. These present as mass-like lesions of considerable length and diameter [32].

Anomalies — Hematomas resulting from trauma during delivery are relatively common

Rare anomalies of the cord sometimes noted macroscopically include teratomas, cysts, and aneurysms [33-38]. All of these unusual findings should be documented by a full histopathologic examination.

Umbilical cord cysts may arise from embryonic remnants of the vitelline duct and urachus. They can occur anywhere along the length of the cord. First trimester umbilical cord cysts noted on ultrasound are often transient and have no clinical significance [39-42]. Persistent cysts have been associated with a variety of fetal anomalies (particularly patent urachus and omphalocele), but the true prevalence of fetal anomalies in these patients cannot be determined from the small retrospective case reports and series that have been published [43].

Preparation for histologic examination — After the gross examination described above has been performed, the cord is transected at the disk and three sections are isolated and placed in formalin for histologic examination; a random piece of cord should also be included. These specimens should incorporate the most distal, most proximal, and mid sections of the cord, as well as any areas that appear abnormal. Cords that are abnormally colored, especially due to meconium, should be extensively sectioned (at least three cassettes). The sections should be labeled so they can be oriented by the pathologist. Abnormalities, such as true knots, should not be sectioned by the clinician so the gross abnormality can be viewed by a pathologist.

7.Kiran H, Kiran G, Kanber Y. Pseudocyst of the umbilical cord with mucoid degeneration of Wharton's jelly. Eur J Obstet Gynecol Reprod Biol 2003; 111:91.
8.Yavner DL, Redline RW. Angiomyxoma of the umbilical cord with massive cystic degeneration of Wharton's jelly. Arch Pathol Lab Med 1989; 113:935.
9.Lacro RV, Jones KL, Benirschke K. The umbilical cord twist: origin, direction, and relevance. Am J Obstet Gynecol 1987; 157:833.
10.Kalish RB, Hunter T, Sharma G, Baergen RN. Clinical significance of the umbilical cord twist. Am J Obstet Gynecol 2003; 189:736.
11.Reynolds SR. Mechanisms of placentofetal blood flow. Obstet Gynecol 1978; 51:245.
12.Georgiou HM, Rice GE, Walker SP, et al. The effect of vascular coiling on venous perfusion during experimental umbilical cord encirclement. Am J Obstet Gynecol 2001; 184:673.
13.Dado GM, Dobrin PB, Mrkvicka RS. Venous flow through coiled and noncoiled umbilical cords. Effects of external compression, twisting and longitudinal stretching. J Reprod Med 1997; 42:576.
14.Rayburn WF, Beynen A, Brinkman DL. Umbilical cord length and intrapartum complications. Obstet Gynecol 1981; 57:450.
15.Naeye RL. Umbilical cord length: clinical significance. J Pediatr 1985; 107:278.
16.Strong TH Jr, Elliott JP, Radin TG. Non-coiled umbilical blood vessels: a new marker for the fetus at risk. Obstet Gynecol 1993; 81:409.
17.Rana J, Ebert GA, Kappy KA. Adverse perinatal outcome in patients with an abnormal umbilical coiling index. Obstet Gynecol 1995; 85:573.
18.Degani S, Leibovich Z, Shapiro I, et al. Early second-trimester low umbilical coiling index predicts small-for-gestational-age fetuses. J Ultrasound Med 2001; 20:1183.
19.de Laat MW, Franx A, Bots ML, et al. Umbilical coiling index in normal and complicated pregnancies. Obstet Gynecol 2006; 107:1049.
20.Predanic M, Perni SC, Chasen ST, et al. Ultrasound evaluation of abnormal umbilical cord coiling in second trimester of gestation in association with adverse pregnancy outcome. Am J Obstet Gynecol 2005; 193:387.
21.Rogers, MS, Ip, YW, Qin, Y, Rogers, SM, et al. Relationship between umbilical cord morphology and nuchal cord entanglement. Acta Obstet Gynecol Scand 2003; 82;32.
22.Schachter M, Tovbin Y, Arieli S, et al. In vitro fertilization is a risk factor for vasa previa. Fertil Steril 2002; 78:642.
23.Englert Y, Imbert MC, Van Rosendael E, et al. Morphological anomalies in the placentae of IVF pregnancies: preliminary report of a multicentric study. Hum Reprod 1987; 2:155.
24.Fujikura T. Fused umbilical arteries near placental cord insertion. Am J Obstet Gynecol 2003; 188:765.
25.Heifetz SA. The umbilical cord: obstetrically important lesions. Clin Obstet Gynecol 1996; 39:571.
26.Stefos T, Sotiriadis A, Vasilios D, et al. Umbilical cord length and parity--the Greek experience. Eur J Obstet Gynecol Reprod Biol 2003; 107:41.
27.Krakowiak P, Smith EN, de Bruyn G, Lydon-Rochelle MT. Risk factors and outcomes associated with a short umbilical cord. Obstet Gynecol 2004; 103:119.
28.Baergen RN, Malicki D, Behling C, Benirschke K. Morbidity, mortality, and placental pathology in excessively long umbilical cords: retrospective study. Pediatr Dev Pathol 2001; 4:144.
29.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.
30.Stempel LE. Beyond the pretty pictures: giving obstetricians just enough (umbilical) cord to hang themselves. Am J Obstet Gynecol 2006; 195:888.
31.Vern TZ, Alles AJ, Kowal-Vern A, et al. Frequency of factor V(Leiden) and prothrombin G20210A in placentas and their relationship with placental lesions. Hum Pathol 2000; 31:1036.
32.Caldarella A, Buccoliero AM, Taddei A, et al. Hemangioma of the umbilical cord: report of a case. Pathol Res Pract 2003; 199:51.
33.Clausen I. Umbilical cord anomalies and antenatal fetal deaths. Obstet Gynecol Surv 1989; 44:841.
34.Carvounis EE, Dimmick JE, Wright VJ. Angiomyxoma of umbilical cord. Arch Pathol Lab Med 1978; 102:178.
35.Ghidini A, Romero R, Eisen RN, et al. Umbilical cord hemangioma. Prenatal identification and review of the literature. J Ultrasound Med 1990; 9:297.
36.Kamitomo M, Sueyoshi K, Matsukita S, et al. Hemangioma of the umbilical cord: stenotic change of the umbilical vessels. Fetal Diagn Ther 1999; 14:328.
37.Kreczy A, Alge A, Menardi G, et al. Teratoma of the umbilical cord. Case report with review of the literature. Arch Pathol Lab Med 1994; 118:934.
38.Lee MC, Aterman K. An intestinal polyp of the umbilical cord. Am J Dis Child 1968; 116:320.
39.Sepulveda W, Leible S, Ulloa A, et al. Clinical significance of first trimester umbilical cord cysts. J Ultrasound Med 1999; 18:95.
40.Rempen A. Sonographic first-trimester diagnosis of umbilical cord cyst. J Clin Ultrasound 1989; 17:53.
41.Skibo LK, Lyons EA, Levi CS. First-trimester umbilical cord cysts. Radiology 1992; 182:719.
42.Ross JA, Jurkovic D, Zosmer N, et al. Umbilical cord cysts in early pregnancy. Obstet Gynecol 1997; 89:442.
43.Zangen R, Boldes R, Yaffe H, et al. Umbilical cord cysts in the second and third trimesters: significance and prenatal approach. Ultrasound Obstet Gynecol 2010; 36:296.

[DrTatyana]

INADEQUATE WHARTON'S JELLY — The amount of Wharton’s jelly is assessed by visualizing a mid segment of the umbilical cord in cross section, measuring the area using the software of the ultrasound machine, and then comparing the measurement with an established umbilical cord area nomogram. Thin cords have vessels that are more vulnerable to compression and have been associated with intrauterine growth restriction and fetal distress during labor.

Sonographic umbilical vessel morphometry and perinatal outcome of fetuses with a lean umbilical cord.Ghezzi F, Raio L, Günter Duwe D, Cromi A, Karousou E, Dürig PSOJ Clin Ultrasound. 2005;33(1):18.

PURPOSE: This study was undertaken to assess whether changes in umbilical cord vessel morphometry are associated with an increased risk of adverse perinatal outcome among fetuses with a lean umbilical cord on sonography.

PATIENTS AND METHODS: A total of 160 fetuses with a sonographically lean umbilical cord (cross-sectional area below the 10th percentile for gestational age) after 20 weeks of gestation were enrolled. The cross-sectional areas of the umbilical cord and its vessels were measured. Outcome variables investigated were perinatal death, admission to the neonatal intensive care unit, intrauterine growth restriction, and 5-minute Apgar score.

RESULTS: The proportions of perinatal death (1/96 versus 6/64, p<0.05) and admission to the neonatal intensive care unit (17/96 versus 22/64, p<0.05) was significantly higher among fetuses with an umbilical vein area below or equal to the 10th percentile for gestational age than among those with an umbilical vein area greater than the 10th percentile. No differences were found in the proportions of perinatal death, neonatal intensive care unit admission, 5-minute Apgar score<7, and intrauterine growth restriction when fetuses with umbilical vein areas below or equal to the 10th, the 5th, and the 2.5th percentiles for gestational age were compared. No difference was found in the umbilical artery area and Wharton's jelly area among the groups.

CONCLUSION: Among fetuses with a sonographically lean umbilical cord, a significant relationship exists between an umbilical vein area below or equal to the 10th percentile and an adverse neonatal outcome.

Department of Obstetrics and Gynecology, University of Insubria-Del Ponte Hospital, Piazza Biroldi 1, 21100 Varese, Italy.

Sonographic measurement of the umbilical cord and fetal anthropometric parameters.Raio L, Ghezzi F, Di Naro E, Gomez R, Franchi M, Mazor M, Brühwiler H
Eur J Obstet Gynecol Reprod Biol. 1999;83(2):131.

OBJECTIVE: To determine reference ranges for the diameter and the cross-sectional area of the umbilical cord during pregnancy and to determine if umbilical cord morphometry is related to fetal size.

METHODS: A prospective cross-sectional study was designed to assess the sonographic cross-sectional diameter and area of the umbilical cord. The sonographic umbilical cord measurements were obtained in a plane adjacent to the insertion of the cord into the fetal abdomen. Nomograms for the umbilical cord diameter and area were computed. Fetal biometry included: biparietal diameter, abdominal circumference, and femur length. Polynomial regression analysis was conducted.

RESULTS: Five hundred and fifty seven patients were included into the study. The regression equation for the umbilical cord diameter (y) according to gestational age (x) was y=-10.0563+1.4265x+0.0194x2 and for the umbilical cord area (y') was y'=91.6-3.3x+0.03x2-0.00007x3. A significant relationship was found between umbilical cord measurements and fetal anthropometric parameters.

CONCLUSION: Reference ranges for umbilical cord diameter and area have been generated. The sonographic diameter and cross-sectional area of the umbilical cord increase as a function of gestational age and both diameter and area correlate with fetal size.

The Department of Obstetrics and Gynecology, Kantonsspital, Münsterlingen, Switzerland.