Naturally produced by the body during labour and lactation, oxytocin is responsible for causing uterine contractions before birth.
It is also known as the hormone of love, trust and bonding.
What is oxytocin?
It is a hormone produced naturally by the brain and more specifically by the pituitary gland, a gland located between the two eyes.
While this happiness hormone is released during emotional relationships and other moments of well-being, it also intervenes in several key phases of motherhood and is important during childbirth.
Considered the hormone of love and happiness, oxytocin is synthesised by the hypothalamus and stimulates milk secretion and uterine contractions.
What is the role of oxytocin in labour?
It is obviously no coincidence that the term "oxytocin" comes from the Greek "õkytokíne", meaning "quick birth".
Oxytocin production gradually increases throughout pregnancy to prepare the uterus for expulsion, peaking during labour when its rate is multiplied by 200.
The hormone helps to ensure a smooth labour by inducing and accelerating contractions.
This hormone also plays an important role after birth.
Oxytocin facilitates the detachment and expulsion of the placenta and, thanks to the contractions it induces, allows the uterus to return to its normal shape.
A natural physiological process called "release" that reduces the risk of bleeding in mothers after giving birth.
Oxytocin injection to speed up labour
To induce labour, or to speed up labour if cervical dilation has stopped, the pregnant woman can be given a low dose of artificial oxytocin intravenously.
The contractions usually become stronger and closer together.
Sensors are used to measure the baby's heart rate and monitor the frequency and intensity of the contractions.
Oxytocin production and lactation
The natural production of oxytocin after birth stimulates milk production.
The baby's sucking reflex when breastfeeding begins then leads to the production of this hormone.
Oxytocin also stimulates the secretion of prolactin, the hormone responsible for initiating and maintaining lactation after birth.
This explains why mothers often experience labour pains when breastfeeding in the first few days after giving birth.
Oxytocin for bonding
The release of oxytocin has a bonding function during pregnancy and birth.
It helps to strengthen the bond between mother and baby.
The skin-to-skin contact that parents practise after birth stimulates the release of this hormone, facilitating a sense of trust.
It also promotes protective and maternal behaviour by increasing the release of dopamine.
According to an Israeli study published in the journal Psychological Science and reported by the science information website PsychoMedia, oxytocin levels are even a predictor of mother-child bonding behaviour from early pregnancy.
After measuring the levels of oxytocin in the plasma of 62 pregnant women during the first and last trimesters, as well as in the month following delivery, the researchers concluded that "oxytocin appears to prepare mothers to engage in attachment behaviours".
This makes it the hormone of motherhood, trust... and love par excellence.