Oxytocin: The Love Hormone
Oxytocin is probably the initiator of labor; the pituitary gland in the brain releases oxytocin that signals the uterus to contract. As the uterus contracts, it releases prostaglandins that soften the cervix and also cause contractions. Then the presence of prostaglandins signals the brain to release more oxytocin, which causes the uterus to contract more, which releases prostaglandins…. And then we enter this positive feedback loop where the presence of one hormone (oxytocin) increases the presence of the other (prostaglandins) that then increases the presence of the initial hormone, and so on.
Oxytocin is known as our love hormone, as it is released when we have loving physical touch, such as hugging or kissing, and creates this anesthesia-like effect when we are in pain. The reception of oxytocin during labor helps to dull the pain of the contractions.
We can enhance the release of naturally occurring oxytocin with loving touch during labor, such as massage, being held by our partners, or hugging. Oxytocin also is released more when we feel safe and supported, so ensuring that those who are around us are contributing in a positive manner will be important. We can enhance the safe feeling by dimming the lights and lowering the volume of our room.
One of my favorite ways to help with oxytocin release if we may be trying to get labor going, is to dim the lights, play quiet music, and then have the partner and myself as the doula massage the mother’s feet as she reflects on how she is mentally feeling about her birth.
If we cannot naturally enhance the release of oxytocin, or labor needs to be augmented for time constraints, then the synthetic version of oxytocin, Pitocin, could be administered to increase labor contractions. It is important to note that we cannot completely replicate any hormone in our body, to include oxytocin, so while it may do something similar (cause contractions) it is not received in our body is the exact same way.
During spontaneous labor, the concentration of oxytocin increases gradually overtime which causes our contractions to build over a period of time. There may be naturally occurring stalls or pauses that our body is trying to take due to the need for rest during labor, that may not be present if labor is augmented with Pitocin. And most importantly, the way we perceive contractions is not altered with Pitocin; oxytocin makes you feel good about your contractions and alters the reception of pain, but since Pitocin does not cross the blood-brain barrier, it does not change our perception of labor pain. Most women will report that contractions with Pitocin feel more intense and painful than spontaneous labor contractions.
Beta-endorphins
Beta-endorphins create a numbing affect to pain. Think when you first cut your hand, it feels painful at first, then it seems to numb itself. This is because of beta-endorphins: they are released when we are in stress, to help increase our tolerance to whatever pain we are feeling to help us in a fight or flight response. This is important during birth!
Beta-endorphins can also create this altered consciousness state, which is prevalent during labor: think about a woman in active labor, she is not quite there anymore, she is in “labor land.” Beta-endorphins help this transition of consciousness. Staying in a more primal state during labor will help this release and that of oxytocin: allow the laboring mother to remain in this state of consciousness without interruption. How could we interrupt this? Asking too many questions; continuing to carry on conversations without regards to protecting the birth space; interrupting labor by trying to rush or “save” it in an attempt to be important.
Catecholamines
These are our stress hormones released during a fight-or-flight response. Important towards the end of labor as a woman is getting ready to push and birth her baby, and tend to be peaked during transition (~8-10cm of dilation). These hormones are important to help baby transition from one environment (the womb) to a completely different one (the world); these hormones hype baby up so that they can breathe, regulate their own blood sugars and body temperature, and so much more! We ask a lot of these little humans in a very short period of time. These hormones help them make this transition.
These hormones are why transition can be more chaotic, confusing, or filled with anxiety or doubt. High levels of this hormone in the last part of labor can contribute towards the fetal ejection reflex, where the mother bears down powerfully and spontaneously pushes her baby out. These levels tend to rise normally, and optimally, in birth that is fairly uninterrupted where the mother feels safe and supported.
If the mother feels unsafe, it can contribute towards a fight or flight response and increase the release of these hormones too soon that may stall labor and stop contractions. Ina May talks about watching an animal give birth that thought it was unobserved. Once the animal noticed her, it stopped it labor and ran away to safety.
The use of pain medication or an epidural may inhibit the release of this hormone, so the fetal ejection reflex may not be overwhelmingly strong. However, in my experience, even mothers with epidurals still feel some sensation of bearing down or pushing when they are 10cm and baby is low, but it is definitely not as a strong of a sensation as a mother who is unmedicated.
There are several hormones that influence labor progress: oxytocin initiates labor, causing the uterus to contract, which then causes prostaglandins to be released that soften the cervix and cause more contractions. This positive feedback loop gradually increases the presence of both hormones, causing contractions to build in intensity over the duration of labor. Beta-endorphins are released to help with pain tolerance in response to stress, but too much could inhibit labor by causing too much “numbing.” Catecholamines peak in the last portion of labor prior to pushing, helping the baby transition from womb to world, and contributes towards the powerful fetal ejection reflex.
We can enhance the release of most of these hormones by supporting the mother in a safe environment that is fairly calm and nonintrusive. She should be supported in the birth of her choosing, surrounded by a team that truly believes in her power to birth her baby in the way she desires.
Learn more in our childbirth education courses on what physiological birth looks like! We break down how to move through labor with science in mind to help you feel more confident and powerful in your labor experience.