Any
stress to the mother stimulates the adrenal glands to pour out catecholemines.
As a result, muscle sphincters tighten down making uterine contractions less
effective and sending blood away from the uterus to the arms and legs preparing
the body for fight or flight. All of this prevents an adequate supply of oxygen
to the big contracting muscle - the uterus.
There
are three muscle layers composing the uterus. The outer muscles contract to
push the baby down, through, and ultimately out of the uterus. The middle
muscles contract to squeeze the blood out of the walls of the uterus and then
relax to allow the blood vessels to fill up again with a fresh supply of blood.
But
when the inner circular muscles contract they close the outlet, maintaining the
uterus in its unemptied shape. Thus, these inner circular muscles must be loose
and relaxed when the long muscles contract to open the womb and push the baby
out.
If
a woman is frightened during labor this inner muscle layer contracts, then the
muscles of the uterus and the muscles that hold it closed are working against
each other.
Whenever
there are two big groups of muscles working against each other they soon begin
to hurt and in a short time the pain becomes very severe. We speak of this as
the fear-tension-pain-syndrome of childbirth. A woman who is afraid and
unconsciously resisting the birth of her baby tightens the circular uterine
fibers which prevents the progress of the birth and increases muscle tension
within the walls of the uterus. This causes nearly all of the pains and
distresses in otherwise normal labor - which describes the labor of about
ninety-five women out of a hundred.