World Health Organization

Care of the Umbilical Cord

A review of the evidence

World Health Organization
Reproductive Health (Technical Support)
Maternal and Newborn Health / Safe Motherhood
Geneva

Opinions vary on what constitutes the best umbilical care. This section reviews the evidence from available studies on cord care and attempts to formulate some recommendations on the basis of the evidence.

Timing of cord clamping

The umbilical cord can be clamped immediately after birth or later. Late clamping after cord pulsations have ceased is the usual procedure in traditional births, and early clamping is common in institutions. The timing of cord clamping may have effects on both mother and infant.

The effects on the mother have been studied in some trials. Although there was some evidence that early clamping reduces the duration of the third stage of labour, there was no significant effect on the incidence of postpartum haemorrhage.^32,33,34 The combined use of oxytocin, early cord clamping and controlled cord traction (active management of the third stage of labour) has been shown in some studies to decrease the incidence of postpartum haemorrhage.^35,36 Although prophylactic oxytocin is effective in reducing the risk of postpartum haemorrhage, doubts remain about combining it with early cord clamping and controlled cord traction, and about the routine use of active management in healthy low-risk women.³⁷ Early cord clamping should be avoided in rhesus negative women as it increases the risk of feto-maternal transfusion. However, allowing free bleeding from the placental end of the cord reduces this risk.^38,39,40

A number of observational studies and trials have been conducted on the effects of the timing of cord clamping on the neonate. Delayed cord clamping results in a shift of blood from the placenta to the infant. The volume transfused varies between 20% and 50% of neonatal blood volume, depending on when the cord is clamped and at what level the baby is held prior to clamping.^41,42,43,44 Trials in which newborns were placed on the mother's abdomen⁴⁵ or on the bed where she lay^46,47 and the cord was clamped only when it stopped pulsating showed that these babies had blood volumes 32% higher than babies whose cords were clamped immediately after birth. Placental transfusion was about 80% at 1 minute and was practically completed at 3 minutes.

There have been concerns that the increase in the newborn's blood volume and red blood cell volume that is associated with delayed cord clamping could result in overload of the heart and respiratory difficulties. These effects have not, however, been demonstrated. In fact, there is probably a self-regulatory mechanism in the infant which limits the extent of placental transfusion.⁴⁷ Moreover, there is evidence that the circulatory system of the newborn is capable of rapid adjustment to an increase in blood volume and viscosity by increased fluid extravasation and dilation of blood vessels.^{46, 48}

Placental transfusion may not occur in the usual manner in newborns with perinatal complications. For example, one study found that blood volume in asphyxiated newborns was high in spite of immediate cord clamping, possibly due to a prepartum redistribution of blood between fetus and placenta.⁴⁹ Delaying cord clamping in these babies may cause hypervolaemia and cardio-respiratory complications, although this has never been demonstrated.

Placental transfusion associated with delayed cord clamping provides additional iron to the infant's reserves and may reduce the frequency of iron-deficiency anaemia later in infancy. This is of particular significance in developing countries where iron deficiency is common. Delaying cord clamping also favours early contact between mother and baby. In addition, it also reduces splashing of blood, which helps protect the birth attendant in areas where HIV infection is common.⁵³

Early cord clamping reduces the extent of placental transfusion to the baby and results in significantly lower haematocrit and haemoglobin levels in newborns.^32,54,55,56 However, these differences diminish quickly over time and become negligible by 3 months of age. Neonatal bilirubin levels are lower after early cord clamping but there is no significant difference in the incidence of jaundice.

The physiological consequences of early as opposed to late cord clamping have been studied even less in the preterm infant than they have in infants born at term. One randomized trial found that vaginally delivered preterm infants who had been held 20 cm below the introitus for 30 seconds before the cord was clamped required fewer transfusions for anaemia and fewer high inspired-oxygen concentrations than infants whose cords had been clamped within 10 seconds. More trials are needed to compare the effects of early versus delayed cord clamping on the major adverse outcomes of preterm infants, such as respiratory distress syndrome, sepsis, intracranial haemorrhage and necrotizing enterocolitis.

In conclusion, there is no clear evidence to favour one practice over the other. Delaying cord clamping until the pulsations stop is the physiological way of treating the cord and is not associated with adverse effects, at least in normal deliveries. Early cord clamping conflicts with traditional beliefs and is an intervention that needs justification. If controlled cord traction after oxytocin administration is practised, early cord clamping is mandatory (the cord should be shielded with a sterile covering to minimize blood spraying during the procedure). More research is needed on the effects of the timing of cord clamping on the preterm infant.

Choice of ties

The cord must be always be ligated or clamped at the baby's side prior to cutting, since leaving it untied can cause excessive bleeding. The usual recommendation is also to ligate at the placental side, although this may be less essential. Not ligating on the mother's side may even be beneficial in some circumstances, such as in the case of rhesus negative mothers.

Many kinds of clamps and ties have been used in institutions to tie the cord and prevent bleeding from the stump. No study has investigated which method is best. Plastic cord clamps effectively close all vessels in the umbilical cord and are easy to use. However, they are more expensive and may not be easily available.

The advantages and disadvantages of simple string ties or tapes have not been evaluated. There are no reservations about their use and they are widely available. The tie should be at least 15 cm in length to allow effective tying, i.e. tight enough to occlude the umbilical vessels in order to prevent bleeding when the jelly shrinks and dries.

No study comparing sterile ties with clean ties or clamps was found. It is generally recommended that the ties/clamps be sterile since they are in contact with a mucous membrane.

Some authors suggest clamping the cord with a rubber band since inelastic tying material such as thread or string may loosen after a day and increase the risk of bleeding and infection. However, an instrument is needed to apply the rubber band. The rubber band must be very small to be effective.

Cutting the cord

A sterile and sharp instrument, such as a new razor blade or scissors, is usually recommended for cutting the cord. Experience with a blunter instrument resulted in more vessel spasm and thus less blood loss.However, using a blunt instrument could possibly result in an increased incidence of infection due to more trauma to the tissues. The cord must always be clamped or tied tightly before cutting.

Length of the cord stump

The recommended length of the stump after cutting is usually 2 or 3 cm. Some authors recommend clamping the cord 3-4 cm clear of the abdominal wall to avoid pinching the skin or clamping a portion of the gut which, in very rare instances, may be inside the cord. A long stump could possibly increase the risk of infection because it is harder to keep clean and dry. However, this has not been demonstrated in any study. In many cultures the custom is to leave the cord long for reasons that are believed to be of vital importance to the newborn (see section on traditional practices above); in such cases, the importance of keeping the cord clean and dry and of not letting it come in contact with urine and faeces should be explained to the family.

Care of the cord stump

Clean cord care at birth and in the days following birth is effective in preventing cord infections and tetanus neonatorum. Clean cord care is accomplished by the maintenance of aseptic technique so that the umbilical cord is uncontaminated by pathogens.

At birth, hands should be washed with clean water and soap before delivery, after any vaginal examination, and again before tying and cutting the cord. The newborn should be laid on a clean surface (such as the mother's abdomen) and the cord should be cut with a sterile instrument.

In the postnatal period, clean cord care includes washing hands with clean water and soap before and after care, and keeping the cord dry and exposed to air or loosely covered with clean clothes. The napkin should be folded below the umbilicus. Touching the cord, applying unclean substances to it and covering it with bandages should be avoided.

Other practices that may reduce the risk of cord infections are the use of 24-hour rooming-in instead of nurseries in institutions (rooming-in also has many other benefits such as facilitating breast-feeding and bonding, and increasing the mother's confidence), and skin-to-skin contact with the mother to promote colonization with non-pathogenic bacteria from the mother's skin flora. Early and frequent breast-feeding will provide the newborn with antibodies to help fight infections.

No study could be identified on methods of cleaning the cord should it become sticky or soiled; using clean water and soap (or just clean water if soap is unavailable) seems the most sensible. Cleaning with alcohol is not recommended as it delays healing and drying of the wound (see information on alcohol in the annex).

Over the years, mothers have been advised not to immerse an infant in a tub for bathing until the cord has separated because it has been assumed that immersing the cord in water would promote infection, prevent drying and delay separation. Daily baths in the form of sponge baths are, however, common practice in many hospitals because they are considered infection control measures. A study comparing daily bathing with no bathing has shown no difference in umbilical cord colonization or infection between the groups, and that immersing the newborn in a tub is not harmful to the cord.⁶⁰ However, the main issue here is thermal protection since bathing the newborn can induce hypothermia. The newborn should not be bathed before six hours after birth, or longer if possible, and measures should be taken to ensure that no heat loss occurs. Current recommendations direct that newborns should not be bathed routinely.

While there is general consensus that clean cord care decreases the risk of cord infection, the application of topical antimicrobials to the cord stump is more controversial. A 1997 systematic review of randomized controlled studies comparing different methods of cord care, was unable to conclude that application of topical antimicrobials is superior to just keeping the cord clean.⁶¹ Studies from developed countries show that in hospital nurseries, the use of an antiseptic on the stump significantly reduces umbilical colonization rates. However, as mentioned earlier, the effect of such agents in reducing cord infections is less clear. Since most infections with hospital-acquired bacteria occur after discharge from the hospital, it is important that the evaluation of regimens for umbilical disinfection should prospectively follow up the infants after discharge. Unfortunately very few studies have done this. Some non-randomized studies that have followed up infants suggest that applying antiseptics to the cord stump reduces staphylococcal infections in the nursery and after discharge.However, one randomized controlled study found no such effect.

According to available studies, chlorhexidine, tincture of iodine, povidone-iodine, silver sulphadiazine and triple dye appear to be of most value in controlling umbilical colonization in hospital nurseries (see annex for more information on individual antimicrobials). Alcohol does not promote drying, is less effective against bacteria than other antimicrobials and delays cord separation. It is therefore not suitable either for cleaning or for routine application to the cord stump. While umbilical disinfection seems to be necessary in hospital nurseries to prevent the spread of bacteria, no studies indicate that this is needed in rooming-in babies or at home where clean cord care is practised.

Studies have shown that antimicrobials prolong the time it takes the cord to separate. The clinical significance of this delay has not been studied, but it appears to be of no medical consequence. However, late separation of the cord is disliked by parents as it worries them and entails more home visits by midwives, thus increasing their workload and the cost of postnatal care.

Another disadvantage of using topical antimicrobials is increased cost. Depending on the products used, the cost of this intervention ranges from about US$ 0.38 to US$ 1.50 for each baby

There are very few studies of the effect that applying antimicrobials to the stump has on the incidence of cord infections in developing countries, either in institutions or at home.

A population-based study in rural parts of Pakistan, where mothers delivered at home under unclean conditions and where living areas are often in close proximity to animals and animal dung, found that the use of a topical antimicrobial on the cord stump at delivery and during the first few days after delivery was highly protective against neonatal tetanus as compared to applying nothing to the wound.

In conclusion, clean cord care practices should be the main focus of any clean delivery and cord care programme. There is not enough evidence to recommend the widespread use of topical antibiotics in developing countries. There is some evidence, however, that they are protective against neonatal tetanus when applied to the cord stump for the first few days. In some high risk areas, especially where the custom is to apply dangerous substances to the stump, it might therefore be useful to advise using a topical antimicrobial as a transitional measure to help wean the community away from harmful substances.The use of antiseptics for cord care at home gives rise to some concern, however. There is a danger that the solutions used could be expired, of inappropriate concentration or contaminated, and may be applied with an unsterile rag. Use of antiseptics at home, and the logistics of supply, therefore need close supervision.