In my view, starting the second stage in a standing position can be seen as a preventive measure against the occurrence of shoulder dystocia. If it does occur, it can be easily corrected without having to perform all sorts of heroic manoeuvres.I've become somewhat obsessed in the last year with giving birth in standing positions. My fascination began when my doula trainer, Mary, shared a handout adapted from an article by Jean Sutton called, "Physiological Second Stage or Birth Without Active Pushing."
Jean Sutton, my doula trainer explained, was an engineer before becoming a nurse/midwife. So she applied her understanding of engineering to the human pelvis and determined the optimal maternal stance for the baby's smooth journey through the birth canal. She argues, "Human birth is an engineering situation . . . . We have tended to ignore the way the maternal pelvis and [fetal] head are designed to interact. Parents should be given the facts about how the process works." She also says, "In a normal physiological birth, the mother has no need to deliberately push her baby into the world." Here are the particulars of achieving this apparently effortless process:
1) Optimum fetal positioning. In order for this smooth "fetal ejection reflex" to occur, the baby should be in the anterior position (facing the mother's back) before the pushing stage begins. The website Spinning Babies has excellent resources for encouraging babies to rotate into this optimal position before and during labor.
2) Supportive environment. The laboring mother needs to have freedom of movement. Jean Sutton recommends having "strongly fixed rails or bars at or above normal waist height." A sturdy support person to hold onto may also be sufficient.
3) Optimum maternal positioning. The laboring mother should be in an upright position--standing or kneeling. The mother's weight should ideally be "in front of her ischial tuberosities" (the bones in your bum)--so the upperbody leaning slightly forward. The mother's hands should be grasped onto something above waist height to release tension in the lower body. Her back arched, head thrown back. If ideally supported, her body will sag and her knees will rotate outwards, and the lower part of the woman's spine which includes the tailbone (the Rhombus of Michaelis) will move backward causing her pelvis to destabilize. Midwifery Today describes this fluid physiological process this way:
The following spontaneous actions then occur: the mother reaches upward for something stable to grasp; her body sags forward and knees roll out; her back arches and she begins to wriggle her lower body; the uterus contracts and forces the baby downward (a series of actions very similar to those during orgasm).Jean Sutton argues that any position raising the knees above the seat, reclining, or squatting will cause the pelvis to be "splinted" and fixed. It is also important that a woman's tailbone be free to flex and move out of the way of the baby's head as it travels down.
A woman reclined in a bed cannot experience this spontaneous, fluid process. She also can't experience it with an epidural. Jean says:
I think we need to get women to understand that, although epidurals are great for pain relief, they actually get in the way of a spontaneous second stage and vaginal birth. In many cases, the reason they've got an epidural is that the baby wasn't in the best position when it started, and the baby in the less suitable positions needs all the space he can get to turn around in.(Source)Jean Sutton also emphasizes that it is crucial to resist the temptation to "help" a woman through this process: "Women may be left with permanent damage if the legs or pelvis are moved at the wrong time or at the wrong angle. It must be understood that the spine has no support once the Rhombus moves."
I've given birth three times. Every time I have been squarely on my tailbone with my knees up... like so...And pushing took a great deal of effort every time. It's my dream to someday experience this spontaneous physiological process as God and nature intended--standing upright!
You may also enjoy this article about the Rhombus of Michaelis and physiological birth by Sara Wickham and Jean Sutton.