You may have heard about this amazing hormone and how it is present in our day to day lives, but how does it work during birth? Dr. Sarah J Buckley, an Australian doctor and researcher, writes beautifully about how our hormones are designed to work in labour and the importance of allowing oxytocin doing its job:

This exquisite hormonal orchestration unfolds optimally when birth is undisturbed, enhancing safety for both mother and baby.

Four of the major hormonal systems are active during labour and birth. These involve oxytocin, the hormone of love; endorphins, hormones of pleasure and transcendence; adrenaline and noradrenaline (epinephrine and norepinephrine), hormones of excitement; and prolactin, the mothering hormone. These systems are common to all mammals and originate deep in our mammalian or middle brain.

For birth to proceed optimally, this part of the brain must take precedence over the neocortex, or rational brain. This shift can be helped by an atmosphere of quiet and privacy with, for example, dim lighting and a little conversation, and no expectation of rationality from the labouring woman. Under such conditions, a woman will intuitively choose the movements, sounds, breathing, and positions that will birth her baby most easily. This is her genetic and hormonal blueprint.

All of these systems are adversely affected by current birth practices. Hospital environments and routines are not generally conducive to the shift in consciousness that giving birth naturally requires. A woman's hormonal physiology is further disturbed by practices such as induction, the use of painkillers and epidurals, cesarean surgery, and separation of mother and baby after birth.

Perhaps the best-known birth hormone is oxytocin, the hormone of love, which is secreted during sexual activity, male and female orgasm, birth, and breastfeeding. Oxytocin engenders feelings of love and altruism; as Michel Odent says, "Whatever the facet of love we consider, oxytocin is involved."

Oxytocin is made in the hypothalamus, deep in our brains, and stored in the posterior pituitary, the master gland, from where it is released in pulses. It is a crucial hormone in reproduction and mediates what have been called the ejection reflexes: the sperm ejection reflex with male orgasm (and the corresponding sperm introjection reflex with female orgasm); the fetal ejection reflex at birth (a phrase coined by Odent for the powerful contractions at the end of an undisturbed labor, which birth the baby quickly and easily); and, postpartum, the placental ejection reflex and the milk ejection, or let-down reflex, in breastfeeding.

As well as reaching peak levels in each of these situations, oxytocin is secreted in large amounts in pregnancy, when it acts to enhance nutrient absorption, reduce stress, and conserve energy by making us more sleepy. Oxytocin also causes the rhythmic uterine contractions of labour and levels peak at birth through stimulation of stretch receptors in a woman's lower vagina as the baby descends.The high levels continue after birth, culminating with the birth of the placenta, and then gradually subside.

The baby also has been producing increasing amounts of oxytocin during labour; so, in the minutes after birth, both mother and baby are bathed in an ecstatic cocktail of hormones. At this time ongoing oxytocin production is enhanced by skin-to-skin and eye-to-eye contact and by the baby's first attempts at suckling.Good levels of oxytocin will also protect against postpartum haemorrhage by ensuring good uterine contractions.

In breastfeeding, oxytocin mediates the let-down reflex and is released in pulses as the baby suckles. During the months and years of lactation, oxytocin continues to act to keep the mother relaxed and well nourished. Oxytocin expert and researcher Professor Kerstin Uvnas Moberg calls it “…a very efficient anti-stress system, which prevents a lot of diseases later on. In her study, mothers who breastfed for more than seven weeks were calmer, when their babies were six months old than mothers who did not breastfeed.

The above was provided courtesy of our friends over at Belly Belly.