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The rise of cesareans and decline of vaginal
births mark a troubling era of intervention-riddled obstetric practice
worldwide. In the United States the cesarean delivery rate
reached 26.1 percent in 2002 (1),
its highest rate ever, and similar increases are occurring in other
countries (2-6).
Along with a technology-driven society, an anti-vaginal birth movement
seems to be underway in the obstetric community. Higher rates of
electronic fetal monitoring, induction, and epidural analgesia have been
implicated in the rise in cesareans, but other factors are fueling the
trend. Randomized controlled trials may be the best form of evidence, but
they are not all without flaws, and some multicenter trials (7,8)
have pushed professional management guidelines and clinical practice
toward higher cesarean section rates. Promotion for elective cesareans
combined with an anti-vaginal-birth theme has become a popular educational
offering at medical conferences (9).
For women who want a vaginal birth after a
previous cesarean (VBAC) or, horrors, a vaginal breech birth, making an
informed choice in this new obstetric era is difficult indeed. Fearful
doctors warn that "the natural process of labor and delivery is fraught
with hazard" (10),
and others claim "it is time to speak out and say that cesarean section is
a normal birth method" (11.their
italics). Revised and biased informed consent forms for VBAC downplay
risks of cesareans. So women often get the impression that elective
cesareans are safer![-]() safer than they really are and safer than vaginal birth; some
want the convenience of a scheduled birth. I have my own bias![-]() not only were my two children born by natural
childbirth, I was "twin A," the breech-presenting offspring of a
successful natural, full-term birth of twins, and 8 years later my
mother repeated the feat with a second pair of twins, "twin A" of whom was
also breech. We would have been cesarean certainties in today's
world.
Anecdotes aside, two new multicenter randomized
controlled trials are getting underway in Canada and
Australia that have the potential, ultimately, to further swell the
numbers of women destined for a cesarean delivery. One of these, by the
Maternal, Infant and Reproductive Health Research Unit (MIRU) of the
University of Toronto, Canada, is a comparison between planned cesarean
section (CS) and planned vaginal birth (VB) for twin pregnancies. Jon
Barrett, principal investigator, described the Twin Birth Study at the
MIRU conference of November 7, 2002, "Choosing Delivery by Caesarean: Has
Its Time Come?" (12).
The study's primary research question is "For twin pregnancies of ![>=]() 32 weeks gestation, where twin A is
presenting vertex, does a policy of planned CS decrease the likelihood of
stillbirth or neonatal mortality or serious morbidity, during the first
28 days after birth, compared to a policy of planned VB?" The
secondary research question is "For twin pregnancies of ![>=]() 32 weeks gestation, where twin A is
presenting vertex, does a policy of planned CS compared to a policy of
planned VB decrease the risk of problematic urinary or faecal/flatal
incontinence for the mother at 2 years postpartum?" Approximately 120
centers from 27 countries are expected to participate, with a planned
sample size of 2800 pregnancies, 1400 per group (12).
It will be interesting to see how the results compare with those from a
recent meta-analysis by the same Toronto researchers, which concluded,
"there is no evidence to support planned cesarean section for twins,"
although it "may decrease the risk of a low 5-minute Apgar score" (13).
The second study is the ACTOBAC Trial (A
Collaborative Trial of Birth After Caesarean), in which women at term with
a previous cesarean section will be randomized to either a vaginal birth
or a planned cesarean (14).
The Maternal and Perinatal Clinical Trials Unit of the University of
Adelaide, South Australia, with principal investigator Caroline Crowther,
will conduct this trial. The primary hypothesis, described in the
information sheet for health professionals, is that "Planned vaginal birth
after caesarean section compared with planned elective repeat caesarean is
associated with an increased risk of death or serious adverse outcome for
the infant." The secondary hypotheses are that "Planned vaginal birth
after caesarean section compared with planned elective repeat caesarean is
associated with reduced risk of serious maternal outcomes up to six weeks
postpartum; decreased physical wellbeing in the woman as measured by pain,
dyspareunia, urinary or faecal incontinence and success at breast feeding;
(and) decreased emotional wellbeing in the woman as measured by quality of
life, anxiety, depression, bonding with the infant and relationship with
her partner" (14).
The rising prevalence of cesareans has provoked
outrage (15-18,20-22).
The American College of Nurse-Midwives expressed alarm that "cesarean
section rates are off the charts and women are being duped in thinking
that this is all right" (17).
As the College asserted, "A cesarean should be the last resort, not merely
an option based on convenience or defensive practice" (17).
A strong editorial published by the Association of Women's Health,
Obstetric and Neonatal Nurses suggests that "a revolution" and system-wide
changes in care are needed to return normalcy to childbearing (18).
Consumer groups are speaking out too (15,20-22)
The International Cesarean Awareness Network, Inc. (ICAN) insists on an
"end to forced cesareans," and "a woman's right to make decisions for
herself and her baby" (20).
ICAN's petition, signed by over 3000 individuals, demanded "an immediate
revision of restrictive and harmful vaginal birth after cesarean (VBAC)
guidelines [19]
published by the American College of Obstetricians and
Gynecologists" (20).
The Coalition for Improving Maternity Services (CIMS), alarmed at the
"overuse" and high rate of cesareans in the United States in 2002 (1),
recently published an important fact sheet, "The Risks of Cesarean
Delivery to Mother and Baby" (21).
In Australia, The Maternity Coalition Inc., a
consumer group that combines CARES SA (Cesarean Awareness Recovery
Education Support South Australia), Birthrites, and Maternity Coalition,
has joined forces in a nationwide campaign to oppose the proposed ACTOBAC
trial, which they fear "will have a huge impact on women's choice and care
in the future" (22).
They claim that the trial is unethical, first, because it will randomize
women to major abdominal surgery in the absence of clinical indications,
and second, because women allocated to the repeat cesarean group who go
into labor spontaneously will receive an emergency cesarean irrespective
of labor progress. The Coalition also claims that the trial "sets women up
to 'fail"' and gives biased information by minimizing risks of cesarean
section. Women in South Australia have a right to be
worried![-]() cesareans in their state jumped to 27.8
percent in 2001, compared with a spontaneous vaginal birth rate of 59.5
percent and VBAC rate of 22.9 percent (5).
High, too, on the agenda of cesarean birth
proponents, in the literature, and at medical conferences is the topic of
preventing pelvic floor damage and urinary and anal incontinence by
elective cesarean section. (Note that this pelvic floor issue used to be
the reason for propagating universal episiotomy in earlier days, also
without good evidence.) Those who favor maternal choice for elective
primary cesarean delivery cite "compelling" supportive evidence for pelvic
floor damage and incontinence, and justify the procedure by stressing the
risks of vaginal birth over those of cesarean birth (23).
A voice of reason suggests, however, that "these adverse side effects
[from vaginal delivery] may be more the result of how current obstetrics
manages the second stage of labor," and urges more research into such
management practices (24).
Evidence on the vaginal-birth side of the debate demands equal attention
and offers less than compelling evidence for elective cesarean
section.
Studying a cohort of 149 nuns in upstate
New York, Buchsbaum et al concluded that the prevalence
of urinary incontinence "in nulliparous, predominantly postmenopausal nuns
is similar to rates reported in parous, postmenopausal women" and that
"these findings appear to be contrary to the conventional wisdom that
nulliparity protects against stress urinary incontinence" (25).
They also reported "we are undertaking a study in which findings on
physical examination and urodynamic results from nulliparous nuns will be
compared with those of their parous biological sisters" (25).
An implication of this National Institutes of Health-funded study, which
is recruiting 100 pairs of sisters, could be "a reduced rate of elective
cesarean deliveries" (26).
In a Norwegian study of 15,307 women, the risk of
urinary incontinence was "higher among women who have had cesarean
sections than among nulliparous women and is even higher among women who
have had vaginal deliveries," but "there was no association of
incontinence with mode of delivery in older age groups" (i.e., over
50 years of age) (27).
The authors concluded that "attempts to prevent both any incontinence and
moderate or severe incontinence in the population by encouraging the use
of cesarean section would have limited effect," and that a previous
substudy also "did not show an association between parity and incontinence
after 65 years of age." The results, therefore, "should not be used
as an argument for the increased use of cesarean delivery" (27).
A recent British study compared 184 primiparas who
had cesarean sections with 100 controls who had a noninstrumental vaginal
birth to determine incidence and severity of anal incontinence (28).
The authors found that "severe anal incontinence followed elective and
prelabor emergency cesarean," and "the risk after elective cesarean is
comparable to that after noninstrumental vaginal delivery with an intact
perineum," concluding that "our study supports those who argue against
routine elective cesarean delivery" (28).
Similar findings were reported in a large Australian study of 1546 women,
in whom pelvic floor morbidity, including anal incontinence, occurred
after cesarean delivery with a prevalence comparable to that after
noninstrumental vaginal birth (29).
The Australian investigators concluded that pregnancy, not childbirth
(unless compounded by instrumental vaginal delivery) was responsible for
the frequency of pelvic floor dysfunction. In a BJOG editorial on the Australian
findings, Grant noted "What is remarkable![...]() is the frequency of pelvic floor dysfunction in the population.
Thus one in eight women who have never been pregnant had some form of
pelvic floor dysfunction, compared with one-half of the women who had a
caesarean section or a spontaneous vaginal delivery and two-thirds of the
women who underwent an instrumental vaginal delivery" (30).
Meanwhile, in the United States,
what is a woman's chance of having a cesarean delivery? Certainly these
days she's at high risk if she's too big or too small; too early or too
late; too old or too fearful; too tired of being pregnant or too tired of
being in labor; if she's having twins, if she's breech, if she's
previously had a cesarean; or if she's due and so is the weekend,
Christmas, Thanksgiving, or New Year's Eve. Then again, she's also at risk
if her doctor is in doubt, scared of a lawsuit, too busy, going out of
town, or convinced that a cesarean is always safer![...]() the reasons go on.
More cesareans beget more cesareans, and more
cesareans mean more risks to the health of mothers and babies. Bernstein
reminds us "One of the most significant risks of cesarean delivery is the
need for a subsequent cesarean delivery![...]() .If elective cesarean delivery becomes an acceptable alternative,
we may never be able to undo the practice" (24).
Perhaps the return to normal childbirth calls for a revolution
indeed. |
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