Since humans are mammals these physiological considerations
suggest that in order to give birth women must feel secure,
without feeling observed, in a warm enough place.
The human handicaps
While the physiological perspective can easily identify the
basic needs of labouring women, it can also make easily understood
the specifically human handicaps in the period surrounding birth.
The human handicaps are related to the huge development of that
part of the brain called the neocortex. It is thanks to our
highly developed neocortex that we can talk, count and be logical
and rational. Our neocortex is originally a tool that serves
the old brain structures as a means of supporting our survival
instinct. The point is that its activity tends to control more
primitive brain structures and to inhibit the birth process
(and any sort of sexual experience as well).
Nature found a solution to overcome the human handicap in the
period surrounding birth. The neocortex is supposed to be at
rest so that primitive brain structures can more easily release
the necessary hormones. That is why women who give birth tend
to cut themselves off from our world, to forget what they read
or what they have been taught; they dare to do what civilized
women would never dare to do in their daily social life (daring
to scream, to swear, to be impolite etc.); they can find themselves
in the most unexpected, often primitive quadrupedal posture;
I heard women saying afterwards: ‘I was on another planet’.
When a labouring woman is ‘on another planet’, this
means that the activity of her neocortex is reduced. This reduction
of the activity of the neocortex is an essential aspect of birth
physiology among humans.
This aspect of human birth physiology implies that one of the
basic needs of labouring women is to be protected against any
sort of neocortical stimulation. From a practical point of view
it is useful to explain what this means and to review the well-known
factors that can stimulate the human neocortex.
Language, particularly rational language is one such factor.
When we communicate with language we process what we perceive
with our neocortex. This implies, for example, that if there
is a birth attendant, one of her main qualities is her capacity
to keep a low profile and to remain silent, to avoid in particular
asking precise questions. Imagine a woman in hard labour, and
already "on another planet". She dares to scream out;
she dares to do things she would never do otherwise; she has
forgotten about what she has been taught or read in books; she
has lost her sense of time and then she finds herself in the
unexpected position of having to respond to someone who wants
to know at what time she had her first contractions! Although
it is apparently simple, it will probably take a long time to
rediscover that a birth attendant must remain as silent as possible.
Bright light is another factor that stimulates the human neocortex.
Electroencephalographers know that the trace exploring brain
activity can be influenced by visual stimulation. We usually
close the curtains and switch off the lights when we want to
reduce the activity of our intellect in order to go to sleep.
This implies that, from a physiological perspective, a dim light
should in general facilitate the birth process. It will also
take a long time to convince many health professionals that
this is a serious issue. It is noticeable that as soon as a
labouring woman is on ‘another planet’ she is spontaneously
driven towards postures that tend to protect her against all
sorts of visual stimulation. For example she may be on all fours,
as if praying. Apart from reducing the back pain, this common
posture has many positive effects, such as eliminating the main
reason for fetal distress (no compression of the big vessels
that run along the spine) and facilitating the rotation of the
baby’s body.
A feeling of being observed can also be presented as another
type of neocortical stimulation. The physiological response
to the presence of an observer has been scientifically studied.
In fact, it is common knowledge that we all feel different when
we know we are being observed. In other words, privacy is a
factor that facilitates the reduction of neocortical control.
It is ironic that all non-human mammals, whose neocortex is
not as developed as ours, have a strategy for giving birth in
privacy - those who are normally active during night, like rats,
tend to give birth during the day, and conversely others like
horses who are active during the day tend to give birth at night.
Wild goats give birth in the most inaccessible mountain areas.
Our close relatives the chimpanzees also move away from the
group. The importance of privacy implies, for example, that
there is a difference between the attitude of a midwife staying
in front of a woman in labour and watching her, and another
one just sitting in a corner. It implies also that we should
be reluctant to introduce any device that can be perceived as
a way to observe, may it be a video camera or an electronic
fetal monitor.
In fact any situation likely to trigger a release of adrenaline
can also be looked at in the framework of factors that tend
to stimulate the neocortex. When there is a possible danger,
it is vital to remain alert and attentive. Another way to conclude
that to feel secure is a basic need.
The mechanical difficulties of the birth of Homo Sapiens are
also related to brain development. At term, the smaller diameter
of the baby’s head (which is not exactly a sphere) is
roughly the same as the larger diameter of the mother’s
pelvis (which is not exactly a cone). The evolutionary process
adopted a combination of solutions in order to reach the limits
of what is possible.
The first solution was to make pregnancy as short as possible,
so that, in a sense, the human baby is born prematurely. Furthermore
we have realized recently that the pregnant mother can, to a
certain extent, adapt the size of the fetus to her own size
by modulating the blood flow and the availability of nutrients
to the fetus. That is why small surrogate mothers carrying donor
embryos from much larger genetic parents give birth to smaller
babies than might have been anticipated.
From a mechanical point of view, the baby’s head must
be as flexed as possible, so that the smaller diameter is presenting
itself before spiralling down to get out of the maternal pelvis.
The birth of humans is a complex asymmetrical phenomenon, the
maternal pelvis being widest transversally at the entrance and
widest longitudinally at the exit. A process of ‘moulding’
can slightly reshape the baby’s skull if necessary.
Our close relatives
When mentioning the mechanical particularities of human birth,
one cannot help referring to and comparing ourselves with our
close relatives the chimpanzees. The head of a baby chimpanzee
at term occupies a significantly smaller space in the maternal
pelvis, and the vulva of the mother is perfectly centered, so
that the descent of the baby’s head is as symmetrical
and as direct as possible. It seems that since we separated
from the other chimpanzees, and all along the evolution of the
hominid species, there has been a conflict between moving upright
on two feet and, at the same time, a tendency towards a larger
and larger brain. The brain of the modern Homo is four times
bigger than the brain of our famous ancestor Lucy. There is
a conflict in our species because the pelvis adapted to the
upright posture must be narrow to allow the legs to be close
together under the spine, which facilitates transfer of forces
from legs to spine when running. An upright posture is the prerequisite
for brain development. We can carry heavy weights on our head
when we are upright. Mammals walking on all fours cannot do
the same. That is apparently why the process of evolution found
other solutions than an enlarged female pelvis in order to make
the birth of the ’big-brained ape’ possible: the
faster our ancestors could run, the more likely they were to
survive.
Why humans are special
Physiologists constantly refer to what they learn from non-human
mammals. This leads to keep in mind the main differences between
human beings and other species. One of the main differences
is that the effects of a disturbed birth process on maternal
behaviour are much more evident at an individual level among
non-human mammals.
Countless animal experiments have confirmed that maternal behaviour
can be dramatically disturbed by general anaesthesia. Almost
a century ago, in South Africa, Eugene Marais was making experiments
to confirm his intuition as a poet that a connection exists
between the pain of birth and maternal love.(1) He studied a
group of sixty Kaffir Bucks, knowing that there had not been
a single instance of a buck mother in the herd rejecting her
young in the previous fifteen years. He proceeded to give the
birthing females a few puffs of chloroform and ether, and noticed
that the mothers refused to accept their newborn lambs afterwards.
Maternal behaviour is also highly disturbed by regional anaesthesia.
In the 1980s, Krehbiel and Poindron studied the effects of epidural
anaesthesia among ewes giving birth.(2) The results of this
study are easily summarized: when ewes give birth with an epidural
anaesthesia, they don’t take care of their lamb.
Today caesareans are common in veterinary medicine, particularly
among dogs. This is possible as long as human beings compensate
for a frequently inadequate maternal behaviour, assist the process
of nursing and provide, if necessary, commercial canine milk
replacers. The effects of a caesarean on the maternal behaviour
of primates are well documented, because several species of
monkeys are used as laboratory animals. This is the case of
the ‘crab-eating macaques’ and the rhesus monkeys.(3)
In these species the mothers do not take care of their baby
after a caesarean; laboratory personnel must spread vaginal
secretions on the baby’s body in order to try to induce
the mother’s interest for her newborn.
We don’t need to multiply the examples of animal experiments
and observations by veterinarians and primate-using scientists
to convince anyone that a caesarean – or just the anaesthesia
that is necessary for the operation – can dramatically
alter the maternal behaviour of mammals in general.
In this regard humans are special. Millions of women all over
the world have taken care of their baby after a caesarean birth
or simply an epidural birth or a ‘twilight sleep birth’.
We know why the behaviour of humans is more complex and more
difficult to interpret than the behaviour of other mammals,
including primates.(4) Human beings have developed sophisticated
ways to communicate. They speak. They create cultures. Their
behaviour is less directly influenced by their hormonal balance
and more directly by the cultural milieu. When a woman knows
that she is expecting a baby, she can anticipate displaying
some maternal behaviour. This does not mean that we cannot learn
from non-human mammals. The spectacular and immediate behavioural
responses of animals indicate the questions we should raise
about ourselves.
Where human beings are concerned, the questions must include
terms such as "civilisation" or “culture”.
For example, if other mammals do not take care of their babies
after a caesarean, we must first wonder: ‘What is the
future of a civilisation born by caesarean?’
References:
1 – Marais EN. The soul of the white ant. Methuen. London
1937.
2 – Krehbiel D, Poindron P. Peridural anaesthesia disturbs
maternal behaviour in primiparous and multiparous parturient
ewes. Physiology and behavior 1987; 40: 463-72.
3 - Lundbland E.G., Hodgen G.D. Induction of maternal-infant
bonding in rhesus and cynomolgus monkeys after caesarian delivery.
Lab. Anim. Sci 1980; 30: 913.
4 – Odent M. The Scientification of Love. Free Association
Books 1999 (2nd ed 2001).
(Click here to go back to the top of the page)
