A nuchal cord is when the umbilical cord is ‘coiled’ around the baby’s neck. Most nuchal cords are single coils and loose. Less common are tight, double or multiple coils (1,2,3).

Various studies have shown nuchal cord to occur:

In 10% ” 37% of all births;
More commonly in male babies;
During pregnancy or labour;
Progressively with longer gestation (1,2,3,4).

Maternity care providers should expect to encounter nuchal cords regularly in their practice (2).

Baby Tyler born with a tight x4 nuchal cord. Babe was pink and breathing spontaneously within a minute, cord intact

Nuchal Cord – Rarely The Cause of Harm

Nuchal cords are rarely found to be the cause of adverse outcomes in studies of pregnancy and birth. Several authors have concluded nuchal cords “ordinarily do no harm” (5,6,7).

Some studies have associated nuchal cord with an increased rate of variable fetal heart rate decelerations during labour, and tight nuchal cords to a higher proportion of fetal distress and low Apgar scores (3,4,8). However, in these retrospective studies the definition of tight nuchal cord were those ‘clamped and cut before delivery of the shoulders’ ” therefore short-term morbidity was more likely caused by the interventions rather than the presence of nuchal cord (3).

To learn more about nuchal cords, how babies can and are born with loose/tight/multiple nuchal cords, and why they are disproportionately associated with risk and adverse outcomes, please read Nuchal Cords: The Perfect Scapegoat.

Ritual and Routine

Many birth practitioners are trained to routinely ‘check’ for a nuchal cord during the second stage of labour, and if present, intervene further by pulling to unloop the cord, or clamping and cutting.

Textbook recommendations to intervene in case of nuchal cords (for normal and emergency births) are based on unevaluated medical literature and lack any references to scientific evidence ” they are ‘ritualised’ practices (1).

The rituals advocated in medical textbooks are:

To conduct a vaginal examination once the baby’s head is born, to feel and check for a nuchal cord.
To pull and unloop the cord over the baby’s head before ‘delivery’ of the shoulders, if the cord is loose.
To attempt to loosen the cord or clamp and cut the cord* before ‘delivery’ of the shoulders, if the cord is tight.

* Some textbooks describe the somersault technique as preferable.

While medical literature from the 1840s onward contains cautionary advice about interfering with nuchal cords, ‘revised’ literature since the 1950s does not (1). Influential nursing and midwifery textbooks that teach nuchal cord ‘management’ also fail to include the findings of research and medico-legal reviews that associate risk, serious injury and malpractice with nuchal cord interventions (1).

Practitioners should know routinely checking, unlooping or cutting a nuchal cord is unnecessary and can have serious consequences for the baby. Women and practitioners should be aware these interventions are usually performed without consent and are contrary to the midwifery model of care (1,2,9).

Vaginal Examination to Check For Nuchal Cord

A vaginal examination to check for nuchal cord occurs at a vulnerable stage for women, when the baby’s head has just been born. In most cases, women are unprepared for this vaginal exam and have not given informed consent (10,11).

Vaginal exams can be painful and distressing for women, but even more so after birthing the head may have caused pain and possible trauma to the perineum. One woman described her experience to Australian midwife researcher Rachel Reed as “fingers of broken glass digging in” (2).

Checking for a neck cord can also interfere with the birth, cause unnecessary stress, and shift a woman’s focus away from giving birth to the intervention being performed (1,2).

No good evidence exists to support the practice of routinely checking for the neck cord, yet it is a common medical birth intervention (9). Jefford and colleagues found it is customary practise in US, UK and Australian maternity units, and taught to students in the UK, US, New Zealand, Ireland, Mexico and Canada. (Interestingly, midwives from Norway and Denmark responding to a survey had not witnessed the practice of checking for nuchal cord) (9).

Pulling and Unlooping a Nuchal Cord

Pulling and looping a nuchal cord over the baby’s head during birth is a common birth intervention (12). Just like checking for cord, it is not based on evidence and there is growing evidence pulling on the cord may be harmful (4).

For example, evidence indicates that handling the cord stimulates the umbilical arteries to vasoconstrict (reducing blood flow) (13). Pulling on the umbilical cord also creates tension that can risk the cord tearing and “subsequent neonatal bleeding” (6). The effect of pulling on the cord is currently unknown and cannot be predicted” cords have snapped as a direct result this intervention, compromising the baby, mother and practitioner (2).

An Australian study has found that once midwives from USA, Australia, Ireland, New Zealand and the UK felt a nuchal cord, they “reverted to carrying out the intervention they had been taught during their training: to clamp and cut the cord” (2,9).

Doctor asks mother to stop pushing and pulls the cord very tight to unloop

Clamping and Cutting a Tight Nuchal Cord

There is no adequate evidence to support routinely cutting a tight nuchal cord (1,2,4,9,14). If the cord is clamped and cut before full delivery has been attempted, on what basis has the practitioner determined the cord was too short or preventing the baby from being born safely? In fact, some of the reasons stated for cutting a tight cord are completely illogical. Surgically clamping and severing the cord does not relieve cord compression or correct a low heart rate/oxygenation ” it produces complete, irreversible ligation and amputates the baby from its only source of blood volume, oxygen and oxygen-carrying red blood cells.

As far back as 1842, medical advice about a cord around the neck “so closely as to strangulate the baby”, was to loosen the cord, or if possible “the cord should be left to see if the baby births” ” only if the birth is prevented may cutting be required (1). The Handbook of Obstetric Nursing text from 1898 began recommending to feel for a nuchal cord but not to cut if one was found ” this advice was continued in midwifery texts until 1930 (1). The 1961 edition of Williams Obstetrics still urged patience after the birth of a baby’s head for the next contractions to ‘deliver’ the shoulders (15). But from 1976 the same book introduced new ideas (without evidence) that if the umbilical cord is tight around the neck, it should be “cut between two clamps and the infant delivered promptly” (15).

When the normal birth process has been “abruptly terminated” a prompt delivery becomes crucial (15, 16). This is not always guaranteed however, and there are number of cases documented in research (Mercer et al) and medical journals where cutting the umbilical cord before delivery of the shoulders resulted in iatrogenic outcomes including cerebral palsy, Erb’s palsy, global developmental delay and death (15).

Although studies show infants may appear to tolerate cutting of a loose nuchal cord, there is clear evidence that cutting of tight nuchal cords before, or immediately after, birth can result in serious injuries and even death (1,14,15). Several writers have observed and documented adverse outcomes as a direct cause of cutting a tight nuchal cord: life-threatening hypovolemia, anaemia, shock, hypoxic-ischemic encephalopathy, cerebral palsy, cognitive deficits and death (8,13,14,15,17,18,19,20).

Clamping and cutting the cord before the shoulders have been born

The major risks of cutting a nuchal cord are associated with the effect of compression on the umbilical cord when the coil is tight and the possibility of a shoulder dystocia (14). Cord constriction from a tight cord can produce a loss of blood volume in the baby and cause acid-base imbalance (due to arteries continuing to send blood away from the baby, but impeding venous return) (14). With cutting of the cord, the baby’s low blood is “fixed” with no recourse to placental transfusion to correct this dangerous condition (14). (Placental transfusion is part of the normal birth process that can reperfusion the baby with oxygenated blood once the baby has been born and compression on the cord is relieved (14)). In serious cases of late-stage cord compression/ tight nuchal cord, babies can be born exhibiting “pallor, irregular respirations, low Apgar scores, gasping, tachycardia, weak peripheral pulses, hypotension, and acidaemia” (21). With the cord already severed, these babies are unable to receive placental transfusion and correction of these conditions.

In 1991, the somersault manoeuvre was first described as an option for ‘managing’ a tight cord without cutting (6). Although not an evidence-based practice, the somersault manoeuvre preserves the normal anatomy and physiological processes of birth by keeping the cord intact ” which is necessary for placental transfusion during the third stage of labour/ neonatal transition and vitally important for the baby born deplete in blood volume (14).

The Somersault Technique promoted to assist births where the cord is short and/or tight

CONCLUSION

Routine checking and intervening with nuchal cords, without evidence it is beneficial or required, is in stark contrast to the philosophy of evidence-based practice ” and particularly the midwifery model of care of non-intervention in normal physiological birth.

Practitioners that respond clinically, not routinely, to a cord ” and with the least intervention possible ” are more likely to protect normal physiology and anatomy and avoid iatrogenic injury.

When practitioners begin to observe babies being born with a cord without intervention, they will also cease to routinely check for nuchal cord ” thus sparing women the indignity, pain and distraction of a vaginal exam as their baby is being born.

Until cord ‘management’ ceases to be routine practice, women are best advised to discuss these interventions with their care providers. Women can insist upon interventions being performed only when required and where supported by evidence. Birth partners and doulas should also be aware of nuchal cord rituals and have a clear understanding of the woman’s preferences for the second and third stages of her labour.