Umbilical cord clamping in term deliveries: the RCOG perspective

Dr Anna DavidReader and Consultant in Obstetrics

and Maternal Fetal MedicineUCL Institute for Women’s Health

Cut cord between clamps

The transition from fetal to neonatal life

Placenta

Umbilical cord

Uterus

Clamping and cutting the cord is necessary to separate the placenta from the baby after birth

The time taken to do this is variable

The placental transfusionUterus

Umbilical cord

Placenta

After birth the uterus continues to contract and blood continues to flow from the placenta in the umbilical vessels to the newborn infant for a few minutes after birth.The additional blood volume is the placental transfusion.

For a term newborn, the placental transfusion gives an additional 80–100ml of blood.

Newborn

Immediate cord clamping deprives the infant of 20–30 mg/kg of iron, sufficient for the needs of a newborn infant for around 3 months

Historical perspective on cord clamping

• Cord clamping or tying became routine in late 1600s

• The reasons given for its use vary– Avoid blood loss from the cord before physiological

closure of the umbilical vessels– Prevent soiling of bed linen– Reduce the chance of infection or contamination of the

baby• By 1960s, cord-clamping by 1 minute of age was

routine, and was performed before the Apgar score was assessed.

Active vs physiological 3rd stage• 3rd stage is from birth of the baby to birth of the placenta• Expectant or physiological management – Allow cord to stop pulsating naturally– Expel placenta by maternal effort

• Traditional active management aims to reduce the risk of pospartum haemorrhage, a complication of childbirth which accounts for almost one quarter of all maternal deaths worldwide.– Drugs to contract the uterus– Early cord clamping and cutting– Traction on the cord to deliver

Active vs physiological 3rd stage• 3rd stage is from birth of the baby to birth of the placenta• Expectant or physiological management – Allow cord to stop pulsating naturally– Expel placenta by maternal effort

• Traditional active management aims to reduce the risk of postpartum haemorrhage, a complication of childbirth which accounts for almost one quarter of all maternal deaths worldwide.– Drugs to contract the uterus– Early cord clamping and cutting– Traction on the cord to deliver

Factors that influence the placental transfusion

• How hard the uterus squeezes the placenta– Intravenous ergotamine causes a rapid uterine

contraction– Placental transfusion is complete by 1 minute with no

difference in the final volume of transfusion– Intramuscular drugs are now preferred which leads to

uterine contraction after 2.5 minutes (oxytocin) or ergometrine (7 minutes)

– Neither intramuscular oxytocin or ergometrine are likely to have an effect on placental transfusion.

• Gravity– Only has an effect if the baby is held at least 20cm

above or below the woman.

Time to clamping

Time to clamping

• Based on evidence from systematic review (Cochrane 2008)– ‘Early’ cord clamping: within 60 seconds of birth– ‘Delayed’ cord clamping: >1 minute or when cord

pulsation has ceased– 11 trials of 2989 mothers and babies

• Recently updated Cochrane review does not change their conclusions

Time to clamping: Maternal outcomes

No effect•No significant differences in postpartum haemorrhage, need for manual removal of placenta, need for uterotonics (drugs to contract the uterus), need for blood transfusion, delayed 3rd stage

Time to clamping: Neonatal outcomesA mixed picture•Significant increase in newborn haemoglobin level in late compared with early cord clamping – Weighted mean difference 2.17 g/dL (95%CI 0.28 to 4.06), 3

trials of 671 infants– Haemoglobin effect did not remain past 6 months of age– Infant iron stores remained increased at 6 months of age

•Significantly more phototherapy for jaundice in the late compared with early clamping – RR 0.59 (0.38 to 0.92); five trials of 1762 infants– Equates to 3% of infants in the early clamping group and 5%

in the late clamping group, a risk difference of 2% (95%CI -0.04 to 0.00)

Time to clamping: Neonatal outcomes• Insufficient data for reliable conclusions about the

comparative effects on other short-term outcomes– Symptomatic polycythaemia (high red blood cell

concentration)– Respiratory problems– Hypothermia– Infection– Need for admission to special care

• No data on long term outcomes– Infection, neurodevelopment etc

The potential for harm needs to be weighed up by clinicians in context

with the settings in which they work

Reduced iron status vs Jaundice

• Iron deficiency in the first few months of life is associated with neurodevelopmental delay, which may be irreversible.– Further research is needed to determine the impact of

time to cord clamping on iron stores and neurodevelopmental delay

• Untreated chronic neonatal jaundice is associated with brain damage (kernicterus)– Access to phototherapy may be challenging in some

countries

Immediate cord clamping became routine practice without rigorous evaluation.

Large randomised trials comparing the effects of timing of cord clamping are needed, with

assessment of substantive outcomes and long-term follow-up for both mother and

baby.

Current WHO position

• Basic Newborn Resuscitation Guideline 2012• “In newly-born term babies who do not require

positive-pressure ventilation, the cord should not be clamped earlier than one minute after birth”

• Strong recommendation based on evidence of high to moderate quality

• WHO Recommendations for the prevention of postpartum haemorrhage state that the cord should not be clamped earlier than is necessary for applying cord traction (around 3 minutes)

• The RCOG recommends that the time at which the cord is clamped should be recorded.

• The cord should not be clamped earlier than is necessary, based on clinical assessment of the situation.

• Delayed cord clamping (more than 30 seconds) may benefit the neonate in reducing anaemia ……

• RCOG will review document taking into consideration the updated Cochrane review, and data emerging from long term outcome studies eg follow up to Swedish study in 2011• The current recommendation is that the cord should

not be clamped “earlier than necessary” and “delayed cord clamping of >30 seconds” may benefit the baby