The main cause of pain in a normal childbirth is what Dr. Grantly DickRead (the "father" of modern natural childbirth) called the "Fear-Tension-Pain-Syndrome." Relaxation is the key to pregnancy, Labor, birthing, and breastfeeding.
Despite the fact that we have technology at our disposal, our biology provides us with powerful instincts during birth. The first is the need to feel safe and protected. All mammals will instinctively seek out a dark, secluded, quiet, and most of all, safe place in which to give birth. While birthing, mammals give the appearance of sleep and closed eyes to fool would-be predators, and they breathe normally. Some (those who don't perspire) will pant in order to cool down, but humans will most easily achieve a relaxed state through closed eyes and abdominal breathing. This relaxation slows down the birthing mother's brain waves into what is called an alpha state, a state in which it is virtually impossible to release adrenaline, the "fright-flight" hormone. Physical comfort becomes critical, along with the need to have a "nest" ready for the baby. Hospital environments often unintentionally disrupt the birthing atmosphere by introducing bright lights, lots of people, noise, and fear-inducing exams and machines. Put it all together and you have fear, and therefore stress, and stress causes pain.
The uterine muscles are beautifully designed to deal quite effectively with danger, fear, and stress in Labor. The uterus is the only muscle in the body that contains within itself two, opposing muscle groups one to induce and continue Labor and another to stop Labor if the birthing mother is in danger or afraid. Emotional or physical stress will automatically signal danger to a birthing mammal. Her Labor will slow down or stop completely so that she can run to safety. In modern times, this goes haywire. We can't run from our fears -- which may include the "horror story" our best friend told us about her birth -- or even from our hospital or physician. Instead, we may release adrenaline, which causes the short, circular muscle fibres in the lower third of the uterus to contract. These muscles are responsible for stopping Labor by closing and tightening the cervix. The result is that we literally "stew" in our own adrenaline. At the same time that the long, straight muscle fibres of the uterus are contracting to efface and dilate the cervix, the short, circular muscle fibres of the lower uterus are also contracting to keep the cervix closed and "fight" the Labor. The result? The very real pain of two powerful muscles pulling in opposite directions each time the birthing mother has a contraction.
Anything causing fear in the birthing mother will increase her pain, a pain often described later as "Labor from hell." The constant presence of a loving, supportive, and trained Labor coach; effective education about the birthing process; and a physician and birthing environment the birthing mother can trust can make all the difference in the world. By learning to deeply relax mentally, physically, and emotionally; actively dealing with fears about birth; and choosing a birthing environment that feels safe and protective, birthing women will not have to experience the traumatic pain caused by the "Fear-Tension-Pain-Syndrome." In such a positive mental, physical, and emotional environment, Labor can feel very, very different.
Unnecessary or preventable pain can also be caused during Labor by simple things such as prohibiting the labouring mother from walking, changing positions, or moving around freely according to her instincts. Freedom of movement literally supports rotation and alignment, the process by which the baby turns and moves down through the pelvic inlet and outlet. Time-honoured traditions in birthing have always included walking, changing positions, rocking, and even floating in water. Anything that assists the rotation and alignment of the baby during Labor will automatically improve the efficiency of contractions, thereby shortening Labor and decreasing pain.
Avoiding unnecessary medical interventions during Labor will decrease pain because these interventions (such as breaking the water, or using Pitocen) actually cause pain themselves, leading to routine epidurals. The use of these regular interventions interferes with the natural process of birth, which is inherently safe and effective. When the natural process is interfered with, pain is the result. How is it possible to know whether medical interventions are unnecessary? The answer is surprisingly simple. If both mother and baby are doing fine during Labor, they're unnecessary.
Proper and adequate nutrition during pregnancy and eating and drinking to appetite during Labor can also dramatically decrease pain. A uterus that did not receive adequate nutrients for growth to full-term size can be weak and ineffective during Labor. A weak uterine muscle working far beyond its capacity will result in painful contractions. Inadequate consumption of complex carbohydrates and water during Labor can result in dehydration and low blood sugar, both of which cause more painful and less effective contractions similar to the way a marathon runner "hits the wall." And yet, often hospitals or physicians order routine IVs and "nothing by mouth" once a labouring woman is admitted to the hospital, whether she is at risk or not. If the mother and baby are both healthy and low-risk and are doing well during birth, the mother may experience a less painful Labor by eating and drinking lightly, guided by her appetite and thirst.
A safe and effective exercise program during pregnancy should include aerobic conditioning, to provide the mother with needed endurance during Labor, as well as pregnancy-specific exercises to prepare her body physically for Labor. When the mother's body is strong and prepared, pain is decreased. She will have the strength and endurance for pushing in second-stage Labor, perhaps decreasing the length of the pushing stage, and thereby decreasing pain. Pregnancy-specific exercises include pelvic rocking, Kegel exercises, squatting for Labor, "tailor" sitting (sitting "Indian style" on the floor), and abductor-strengthening (legs apart) exercises. These exercises are taught in good prenatal exercise and childbirth classes and should be done every day during pregnancy.