Home Birthspirit. In this review of newborn and maternal physiology following birth, Dr. Sarah J Buckley focuses on the importance of supporting the newborns transition by delayed, or no, umbilical cord clamping. The third stage of labour, delayed cord clamping or, simply, non interventionist birth The third stage of labour is a powerful and mysterious time more important than we acknowledge and more complex than we know. These thirty minutes or so, which begin as the mother births her baby and finish as she births her babys placenta, are usually uneventful compared to the drama of labour and birth, leading many including many care providers to think that the birth is already completed. However, enormous changes are happening in the brain and body of mother and baby, all of which are crucial for their survival in the short, medium and long term. The substantial contribution of the third stage to species survival predicts that evolutionary investment will be high, with substantial sophistication incorporating multiple systems and adjustments. For the mother, the major adjustment is the shift from pregnant to non pregnant and especially the sudden separation of her babys placenta, which has been intimately associated with her cardiovascular system for the duration of her pregnancy. As the babys placenta peels off her shrinking uterine wall, rather like a postage stamp peeling off a deflating balloon, she must seal the blood vessels on her side so that her uterine blood supply, flowing at one half to one litres per minute, will not haemorrhage from the torn vessels. This physiological miracle is accomplished by the mothers uterine muscle fibres, which begin to contract and retract immediately after birth forming living ligatures that tighten like a purse string, kinking and sealing off each maternal arteriole. The uterine contractions that provoke this life saving haemostatis are triggered by surges of oxytocin, released in a crescendo from the new mothers pituitary as she gives birth. Ongoing maternal pulses of oxytocin are released as she gazes at and touches her baby, and as her newborn massages, licks, and finally suckles her breast Matthiesen et al 2. Maternal oxytocin levels peak around the time of placental expulsion Nissen et al 1. Nelson Panksepp 1. Other hormonal systems are also active in the new mothers brain and body to adapt her to her new maternal role.
Issuu is a digital publishing platform that makes it simple to publish magazines, catalogs, newspapers, books, and more online. Easily share your publications and get. Singapore Art the online archive of Singapore art works and news. These include beta endorphin, the bodys natural opiate and a hormone of attachment, which peaks at birth adrenaline and noradrenaline, which are elevated in the minutes after birth and ensure that both mother and baby are wide eyed and alert at first contact noradrenaline is also a hormone of attachment Nelson Panksepp 1. Grattan 2. 00. 1 likely also beginning its role as the major hormone of breastmilk synthesis during and soon after labour and birth. Postpartum elevations of these hormones, which are even higher and more sustained within the brain than levels measured in the bloodstream Gimpl Fahrenholz 2. Pedersen Boccia 2. Newborn and maternal hormone elevations in the hour following birth also ensure an optimal start to breastfeeding, as initiated by the baby and supported physiologically, hormonally, and behaviourally by the mother Buckley 2. For the baby, the major changes during third stage involve the respiratory and cardiovascular systems. These two immediate adjustments, both crucial for survival, are interrelated and both require the extra volume of blood that Mother Nature provides for an optimal newborn transition. An ongoing supply of oxygen is a physiological necessity, and so, beginning at birth, blood is rerouted away from the placenta which is reducing its oxygenating capacity and towards the newly functioning lungs. Over this time, the pulmonary blood flow increases from 8 percent of foetal cardiac output to 4. Newborn circulatory rerouting involves the closure of the shunts from umbilical cord to liver and heart, ductus venosus from right to left atrium foramen ovale and from pulmonary trunk to descending aorta ductus arteriosus, most of which are aimed at supporting the new pulmonary circuits. Other major roles of the placenta, chief waiter in the hotel de womb, must also be performed by the newborn kidney, liver, gut, and skin. These newly functioning organs, whose vascular beds were relatively unfilled in utero, also require extra blood for optimal perfusion and function. Mother Natures superb design for this time involves a gradual redistribution of blood in the minutes after birth, adding up to a substantially increased blood volume in the newborn, compared to the foetal, body. This haemotological top up, known as the placental or placento foetal transfusion, comes from blood that is temporarily held in the placenta and is transferred to the newborn in several stages. According to Dunn 1. The higher pressure artery is not affected, so that blood can flow from baby to placenta but not back again. This placental back log may help to delay placental detachment by making the placenta more rigid. Delayed detachment gives the newborn an ongoing source of oxygenated placental blood that is an important back up, especially if the baby is slow to breathe. Observations that the first five or so newborn breaths are not effective in gas exchange Ullrich Ackerman 1. Marquis Ackerman 1. As the baby emerges, pressure on the umbilical vein is released and the bolus around 6. L of warm, oxygenated, p. H balanced blood that was back logged in the placenta enters the babys circulation Dunn 1. This occurs within seconds of birth, as evidenced by two studies in which weight gain reflecting incoming blood has been continuously recorded from birth Diaz Rossello 2. This placental transfusion, also called the placento foetal redistribution, is augmented by the new mothers third stage contractions, which compress the in utero placenta and so push blood towards the baby. Between contractions, blood can return from baby to placenta through the umbilical vein, which closes later than the artery, and which can transport blood in either direction. This transfusion takes place over several minutes, with the majority of blood transferred within three minutes of birth. The final amount of blood that is transferred from placenta to newborn can vary from 5. L Usher et al 1. This may happen through adjustment of umbilical vein flow or other means Gunther 1. The average newborn blood gain following the placental transfusion is around 1. Diaz Rossello 2. This is around one third of the total blood volume of an average term newborn 3. This blood is also rich in protein and nutrients containing, for example, the equivalent iron in 1. Zlotkin 2. 00. 2 in red cells delayed clamping increases red cell numbers by up to 6. Yao et al 1. 96. The deliberate withholding of newborn blood for so called cord blood banking, which involves taking all or most of this 1. Diaz Rossello 2. Buckley 2. 00. 9. The extra blood volume, as well as its components, is also important for an optimal transition. Mercers model of neonatal transitional physiology Mercer Skovgaard 2. According to studies by Jaykka 1. The placental transfusion also aids the clearance of the fluid that fills the foetal lungs, which is optimized by the high levels of plasma proteins associated with a full placental transfusion. Good levels of plasma proteins ensure that the blood colloid osmotic pressure COP is high enough to pull the more dilute lung fluid across the alveolar membrane and into the blood stream by osmosis. Both volume and COP effects will optimize newborn lung function, and may be compromised by early clamping. The baby whose cord is clamped immediately after birth, especially within the first ten to twenty seconds, will lose not only the nutrients, stem cells, and red cells, but also the extra blood volume and will be hypovolemic, to a greater or lesser extent Dunn 1. Diaz Rozello 2. For the neonate, it is as if 2. Recent randomized controlled trials of early versus delayed cord clamping have highlighted the extra risks of iron deficiency and anaemia in infancy associated with early clamping, compared with a delay of even 3.