Here is a very interesting quote! It explains that birthing environments in which a mother feels inferior to the 'important experts' can actually inhibit the progress of her labour, because feeling dominated suppresses oestrogen levels. That's why it is important to choose a birth place where you feel relaxed and confident, that you will be heard, respected and deferred to by all those present in your birth space.

Here's the quote:

"It has been shown that social subordination (feeling dominated by, or inferior to someone) can suppress estrogen levels as effectively as the removal of ovaries (Robert M. Sapolsky, Why Zebras Don't Get Ulcers, W. H. Freeman & Company, 1998). Since a rise in estrogen is known to be the central key for normal labor and delivery, if a woman giving birth feels dominated by her doctor or midwife, this alone can alter the course of her labor.

"This could explain why some women report feeling a change in the "energy" when a doctor or midwife enters the room. If the laboring woman views this person as an authority figure, her estrogen levels can literally plummet. Without estrogen, the fibrous tissue cannot soften and childbirth becomes impossible. Estrogen is also needed to close the womb. So when a midwife or doctor claims they have prevented a woman from hemorrhaging, they have no way of knowing if the hemorrhage would have occurred if they hadn't been at the birth.

"And stress certainly suppresses estrogen secretion. As noted in Chapter 3, Jay Kaplan has shown that the stressor of social subordinance in a monkey can suppress estrogen levels as effectively as removing her ovaries. Given these findings, it is relatively easy to see how stress disrupts sexual behavior in a female."

"After reading this I did a search on "estrogen in childbirth" and found the passages below:

"The rise in estrogen is the central key for normal labor and delivery, a context within which it becomes interesting to look at environmental factors and environmental disruptions, including stress hormones."
Page 31
The Role of Environmental Hazards in Premature Birth: Workshop Summary
The Role of Environmental Hazards in Premature Birth: Workshop Summary (2003)
Board on Health Sciences Policy (HSP)
Institute of Medicine (IOM)
Authors:
Donald R. Mattison, Samuel Wilson, Christine Coussens, and Dalia Gilbert, Editors, Roundtable on Environmental Health Sciences, Research, and Medicine

"The softening and dilation of the cervix is reliant on estrogen, as is the production of proteins that encourage contractions. The ability of the mother's blood to coagulate during the birthing process depends on estrogen; so does the production of prostaglandin and oxytocin receptors. Without these, vaginal childbirth would be impossible, for it's only after estrogen makes the mother's uterus more suspectible to oxytocin ? and oxytocin and prostaglandin then stimulate the contractions of smooth muscles in the uterine wall ? that the whole choreography of labor can genuinely begin.
A Baby's View of Birth
By Beth Kephart
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