Research on Posterior Position
Posterior Position and the Fetus Ejection Reflex
Two facts that were the basis of my empirical attitudes [regarding posterior
position] have been authoritatively confirmed by published prospective
studies.
The first fact is that worrying pregnant women about the position of their
baby in the womb is useless. A large Australian randomized controlled trial
involving 2547 pregnant women has eloquently demonstrated that hands and
knees exercise with pelvic rocking from 37 weeks' gestation until the onset
of labor does not reduce the incidence of persistent occiput posterior
position at birth.
The second fact is that fetal position changes are common during labor, with
the final position established close to delivery. This is the conclusion of
a prospective study of 1562 women to evaluate changes in fetal position
during labor by using serial ultrasound examination. Among babies who were
posterior late in labor, only 20.7% appeared to be posterior at delivery.
Finally, when the mother had no epidural, the overall rate of posterior
position at delivery was only 3.3%, although this study was conducted in
conventional departments of obstetrics, where the basic needs of birthing
women could not easily be met. The rate was 12.9% in the epidural group.
When taking into account these two well-documented facts, focusing on the
right question becomes easy: what factors can influence the rotation process
during labor?
The answer is simple: The factors that can facilitate the rotation process
are those that make a typical fetus ejection reflex possible.The passage
toward the fetus ejection reflex is inhibited by any interference with the
state of privacy. The ejection reflex does not occur in the presence of a
birth attendant who behaves like a "coach," an observer, a helper, a guide
or a "support person."
The fetus ejection reflex can be inhibited by a vaginal exam, by an
eye-to-eye contact or by the imposition of a change of environment. It does
not occur if the intellect of the laboring woman is stimulated by rational
language (e.g., "Now you are at complete dilation; you must push"). It does
not occur if the room is not warm enough or if the lights are bright. The
best situation I know for a typical fetus ejection reflex is when no one is
around but an experienced, low profile, silent, motherly midwife sitting in
a corner and knitting.
The image of the "knitting midwife" should not be understood in a literal
sense. Instead, it symbolizes the authentic midwife as a protective mother
figure whose own level of adrenaline is maintained as low as possible.
Noticeably, when the conditions for an ejection reflex are met, most
birthing women find spontaneously complex and asymmetrical bending-forward
postures that probably play an important part in facilitating the rotation
of the baby's head.
Persistent posterior position at birth will become exceptionally rare on the
day when the meaning of privacy is understood and authentic midwifery has
been rediscovered.
- Michel Odent, MD, excerpted from "Occiput Posterior Position Should Be
Exceptionally Rare at Birth," Midwifery Today Issue 76
