A nuchal cord is when the

umbilical cord In placental mammals, the umbilical cord (also called the navel string, birth cord or ''funiculus umbilicalis'') is a conduit between the developing embryo or fetus and the placenta. During prenatal development, the umbilical cord is physiologic ...

becomes wrapped around the

fetus A fetus or foetus (; plural fetuses, feti, foetuses, or foeti) is the unborn offspring that develops from an animal embryo. Following embryonic development the fetal stage of development takes place. In human prenatal development, fetal deve ...

's neck. Symptoms present in the baby shortly after birth from a prior nuchal cord may include duskiness of face, facial

petechia A petechia () is a small red or purple spot (≤4 mm in diameter) that can appear on the skin, conjunctiva, retina, and Mucous membrane, mucous membranes which is caused by haemorrhage of capillaries. The word is derived from Italian , 'freckle,' ...

, and bleeding in the whites of the eye. Complications can include

meconium Meconium is the earliest stool of a mammalian infant resulting from defecation. Unlike later feces, meconium is composed of materials ingested during the time the infant spends in the uterus: intestinal epithelial cells, lanugo, mucus, amniotic ...

respiratory distress Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing di ...

anemia Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, th ...

, and

stillbirth Stillbirth is typically defined as fetal death at or after 20 or 28 weeks of pregnancy, depending on the source. It results in a baby born without signs of life. A stillbirth can result in the feeling of guilt or grief in the mother. The term ...

. Multiple wraps are associated with greater risk. The diagnosis may be suspected if there is a decrease in the baby's heart rate during delivery. Nuchal cords are typically checked for by running the finger over the baby's neck once the head has delivered.

Ultrasound Ultrasound is sound waves with frequency, frequencies higher than the upper audible limit of human hearing range, hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hea ...

may pick up the condition before labor. If detected during delivery, management includes trying to unwrap the cord or if this is not possible clamping and cutting the cord. Delivery can typically take place as normal and outcomes are generally good. Rarely long term brain damage or

cerebral palsy Cerebral palsy (CP) is a group of movement disorders that appear in early childhood. Signs and symptoms vary among people and over time, but include poor coordination, stiff muscles, weak muscles, and tremors. There may be problems with sensa ...

may occur. Nuchal cords occur in about a quarter of deliveries. The condition has been described at least as early as 300 BC by

Hippocrates Hippocrates of Kos (; grc-gre, Ἱπποκράτης ὁ Κῷος, Hippokrátēs ho Kôios; ), also known as Hippocrates II, was a Greek physician of the classical period who is considered one of the most outstanding figures in the history of ...

Signs and symptoms

Symptoms of a prior nuchal cord shortly after birth in the baby may include duskiness of face, facial

, and bleeding in the whites of the eye. Complications can include

respiratory disease Respiratory diseases, or lung diseases, are pathology, pathological conditions affecting the organs and tissues that make gas exchange difficult in Breathing, air-breathing animals. They include conditions of the respiratory tract including the t ...

, and

still birth Stillbirth is typically defined as fetal death at or after 20 or 28 weeks of pregnancy, depending on the source. It results in a baby born without signs of life. A stillbirth can result in the feeling of guilt or grief in the mother. The term i ...

. File:SubConjNuchal.gif, Petechiae and

subconjunctival bleeding Subconjunctival bleeding, also known as subconjunctival hemorrhage or subconjunctival haemorrhage, is bleeding from a small blood vessel over the whites of the eye. It results in a red spot in the white of the eye. There is generally little to no ...

due to tight nuchal cord File:PetechiaNuchal.gif, Petechiae on face due to tight nuchal cord File:FacialDusky.gif, Facial duskiness due to tight nuchal cord File:AbrasionNuchal.gif, Abrasion from a nuchal cord

Diagnosis

In 1962, J. Selwyn Crawford MD from the British Research Council defined a nuchal cord as one that is wrapped 360 degrees around the fetal neck. Crawford commented "It is all the more remarkable, therefore, that little work has been done. to analyze its effects during labor and delivery". To date, there is no prospective case control double-blind study looking at nuchal cords and observational studies vary in opinion as to the degree of poor outcomes. Also not included in these studies is which umbilical cord form (of the 8 different possible structures) was considered a nuchal cord.

diagnosis of a cord around the neck was first described in 1982. “Coils occur in about 25% of cases and ordinarily do no harm, but occasionally they may be so tight that constriction of the umbilical vessels and consequent hypoxia result.” Williams Obstetrics 16th Edition, has only one single sentence in the entire textbook regarding cords around the neck. By contrast, the First Edition of the Encyclopædia Britannica from 1770 had 20 pages of information about Umbilical Cord Pathology with drawings of Umbilical Cord Entanglement. The

Royal College of Obstetricians and Gynaecologists The Royal College of Obstetricians and Gynaecologists (RCOG) is a professional association based in London, United Kingdom. Its members, including people with and without medical degrees, work in the field of obstetrics and gynaecology, that is ...

has these images on its brochure. There are currently three recent texts on ultrasonography which demonstrate the ability of ultrasound to identify umbilical cord issues with reliability as of 2009. A study published in 2004 was done to establish the sensitivity of ultrasound in the diagnosis of a nuchal cord. Each of 289 women, induced the same day, underwent a transabdominal

ultrasound scan Medical ultrasound includes diagnostic techniques (mainly imaging techniques) using ultrasound, as well as therapeutic applications of ultrasound. In diagnosis, it is used to create an image of internal body structures such as tendons, muscle ...

with an Aloka 1700 ultrasound machine with a 3.5 MHz abdominal probe, using gray-scale and color Doppler imaging immediately prior to induction of labor. Presence of the cord was sought in the transverse and sagittal plane of the neck. A nuchal cord was diagnosed if the cord was visualized lying around at least 3 of the 4 sides of the neck. A cord was actually present at delivery in 52 of the 289 women. Only 18 of the 52 cords or 35% of the nuchal cords were detected on ultrasound done immediately before delivery, and 65% of nuchal cords were not detected. Of the 237 cases where there was no cord at delivery, ultrasound had false positive results, i.e. diagnosed a cord in 44 of the 237 cases (19%) in which there was no cord present at all. In this study, ultrasound was only 35% accurate at finding a single loop, and only 60% accurate at detecting a nuchal cord wrapped multiple times around the neck. In no study was it possible by ultrasound to distinguish between a loose or a tight cord, although at least 3 attempted to do so. Peregrine concludes that ultrasound diagnosis of nuchal cords will only be useful if doctors are able to do so reliably and predict which of those fetuses are likely to have a problem., However, perinatologists routinely look for umbilical cord issues in

monoamniotic twins Monoamniotic twins are identical or semi-identical twins that share the same amniotic sac within their mother's uterus. Monoamniotic twins are always monochorionic and are usually termed Monoamniotic-Monochorionic ("MoMo" or "Mono Mono") twins. ...

. Studies have shown an improvement in outcomes where cord entanglement was prenatally identified in these cases. Ultrasound measurement of the velocity of flow in the cord may be useful in the management of twins and chronically growth-retarded fetuses. Of course this depends on the training of the sonographer. To date there are no ultrasound courses which teach the identification of nuchal cord to physicians or technicians. A recent review by Wilson of the American Academy of Ultrasonography Technicians recommends the documentation of umbilical cord issues.

Classification

* A ''"Type A"'' nuchal cord is wrapped around the neck but is free sliding * A ''"Type B"'' pattern is described as a hitch which cannot be undone and ends up as a true knot. File:NuchalFree.gif, Nuchal cord - free sliding File:NuchalLocked.gif, Nuchal cord - locked pattern

Treatment

Management of a presenting nuchal cord should be tailored to prevent

umbilical cord compression Umbilical cord compression is the obstruction of blood flow through the umbilical cord secondary to pressure from an external object or misalignment of the cord itself. Cord compression happens in about one in 10 deliveries. ...

whenever possible. Techniques to preserve an intact nuchal cord depend on how tightly the cord is wrapped around the infant’s neck. If the cord is loose, it can easily be slipped over the infant’s head. The infant can be

delivered ''Delivered'' is a 1998 thriller/crime film directed by Guy Ferland. A pizza boy finds a murdered man at his next delivery and becomes the murderer's next intended victim. External links * * 1998 films 1998 crime thriller films 1998 comed ...

normally and placed on maternal abdomen as desired. If the cord is too tight to go over the infant’s head, the provider may be able to slip it over the infant’s shoulders and deliver the body through the cord. The cord can then be unwrapped from around the baby after birth. Finally, if the cord is too tight to slip back over the shoulders, one may use the somersault maneuver to allow the body to be delivered. The birth attendant may also choose to clamp and cut the umbilical cord to allow for

vaginal delivery A vaginal delivery is the birth of offspring in mammals (baby, babies in humans) through the vagina (also called the "birth canal"). It is the most common method of childbirth worldwide. It is considered the preferred method of delivery, with l ...

if other methods of nuchal cord management are not feasible.

Prognosis

Retrospective data of over 182,000 births, with the statistical power to determine even mild associations, suggest that a single or multiple nuchal cords at the time of delivery is not associated with adverse perinatal outcomes, is associated with higher

birthweight Birth weight is the body weight of a baby at its birth. The average birth weight in babies of European descent is , with the normative range between . On average, babies of South Asian and Chinese descent weigh about . As far as low birth weight ...

s and fewer caesarean sections in births. Although some studies have found that a tight nuchal cord is associated with short term morbidity, it is unclear whether such outcomes are actually a result of the presence of the nuchal cord itself, or as a result of clamping and cutting the cord

References

External links

{{Certain conditions originating in the perinatal period Complications of labour and delivery Midwifery Wikipedia medicine articles ready to translate