Maternal and neonatal individual risks and benefits associated with caesarean delivery: multicentre prospective study

Further to Consultant Obstetrician Mike Wyldes' comments on his
investigation into the CEMACH dataset ['Elective Caesarean section safest
form of childbirth', above]:-

In April 2008, the UK's Birth Trauma Association also analyzed data
taken from the latest CEMACH report, and found that planned cesarean
delivery had the lowest maternal mortality rate compared with all other
births: "of the 2,113,831 women who delivered a baby after 24 weeks
gestation between 2003 and 2005, one in 10 had a caesarean before labour
had begun. Seven women died, giving a mortality rate of 0.31 per 10,000.
This compared to 74 deaths amongst the remaining women who had a natural
birth or an emergency caesarean section, giving a mortality rate of 0.39
per 10,000."(1)

Certainly, planned cesarean delivery results in greater abdominal
morbidity than PVD, but on the other hand, PVD results in greater pelvic
floor trauma than planned cesarean delivery (see this week's news report
on the U.S. 'Fourth International Consultation On Incontinence (ICI)' for
example(2) and my comment on the cesarean benefit of protection against
fecal incontinence(3)).

Women should be honestly informed of each set of birth risks and
benefits, supported during their decision-making process and have their
final choice respected - whether it's vaginal or cesarean delivery.

Finally on this issue, a 2003 HealthGrades Quality Study(4) in the
U.S. "identified an association with higher vaginal complication rates in
those hospitals that did fewer than expected preplanned cesarean sections"
and likewise, lower vaginal complication rates in hospitals with more
preplanned cesareans than expected. The report said that this finding was
"suggestive of, but not definitive of, inappropriate under-utilization of
preplanned first time C-sections in those hospitals", and that further
studies are needed.

Frustratingly, five years after this report, the debate over planned
cesarean delivery and PVD comparisons remains hampered by a lack of
appropriate and relevant clinical studies.

References:

(1)http://www.telegraph.co.uk/news/uknews/1584671/Women-choosing-
caesarean-have-low-death-rate.html

(2)http://www.medicalnewstoday.com/articles/116063.php

(3)http://www.medicalnewstoday.com/youropinions.php?associatednewsid=116063

(4)http://www.healthgrades.com/media/english/pdf/Patient_Choice_Csection_St...

Competing interests:
I am editor of the website www.electivecesarean.com

Sir,
Caesarean section is the last resort as Mother Nature takes care of the
labour. The doctor's lack of insight and the people's demand to decide the
date time for delivery takes the logic out of decision-making.
Man's defiance to suit his convenience has left him more mechanical than
biological. It is taught in medical schools to wait for as long as
possible unless there are strong indictions to resort to Caesarean
section.In developing countries what was exception earlier has now become
a rule.Studies such as these need to be conducted in such a setting before
jumping to conclusions soon lest the glamour this procedure spoil Nature's
Beauty just for a few pounds more!

Prof Mudassir Azeez Khan

Head,Department of Community Medicine,
Mysore Medical College,
Mysore

Competing interests:
None declared

This study needs to be interpreted with extreme caution when
counselling women who have to decide whether to undertake planned
caesarean section (CS) or not. The data can be represented to show that
among women delivered in Latin America, including those delivered
prematurely and at term, the observed outcomes for delivery by planned CS
versus the alternative (vaginal birth or intrapartum CS) were: 1:2640 v
1:4503 risk of maternal death; 1:37 v 1:134 risk of admission to ICU;
1:102 v 1:199 risk of blood transfusion; 1:285 v 1: 928 risk of
hysterectomy; 1: 39 v 1:85 risk of hospital stay >7 days; 1:570 v 1:172
risk of 3rd or 4th degree perineal laceration or post-partum fistula; 1:
323 v 1:249 risk of fetal death; 1:230 v 1:341 risk of neonatal death.

There are a number of problems with applying these findings to
prospective decision-making in circumstances where planned Caesarean
Section is not considered mandatory e.g. for ‘low-risk’ women and fetuses
at term. Firstly, the exclusion from the study of women who underwent what
the authors term emergency Caesarean Delivery e.g. for fetal distress,
eclampsia, or severe haemorrhage negates any usefulness of the study in
the above-mentioned respect since a woman choosing to deliver by CS at 38
weeks gestation, for example, avoids by that choice the development of
such a complication that may lead to perinatal or maternal death at 39
weeks thereafter unless she was instead to choose induction of labour,
which may or may not be successful and would have its own attendant risks
and drawbacks. Secondly, the reported maternal mortality in a group from
whom most high-risk women had already been excluded is completely out of
line with UK maternal mortality figures of approximately 1: 59,000 of
vaginal births and 1: 12,000 caesarean births (1). This alone demonstrates
either a totally different form of care or demography between the study
group and the UK population. Third, in the above-mentioned decision-making
scenario CS is almost always performed at term. In the study group a
perinatal death rate of 1:323 and neonatal death rate of 1:230 was
reported in a way that suggests that these may have been attributable to
delivery by CS. The authors do not report on the proportion of women in
the study with secure pregnancy dating based upon reliable early
ultrasound scans, but if such scans are not universal in Latin America
inaccurate estimation of gestation could potentially be an important cause
of morbidity among women delivered by planned CS. These deaths would be
expected to be almost totally avoidable among low-risk babies with secure
pregnancy dating and delivered by CS at term in the UK, thus tipping the
balance strongly in favour of planned CS where fetal outcome is of
especially high significance e.g. older women with a history of
subfertility. Fourthly, the report of a 1:172 risk of 3rd or 4th degree
tears or vaginal fistula among the vaginal delivery group is 7 times lower
than other reported estimates for the clinical diagnosis of such injuries
(2), and even further out of line with data based on objective
investigations (3).

The study is interesting for highlighting some differences between
obstetric practices and outcomes between Latin America and the UK but of
little relevance to UK practice and the ongoing debate regarding the risks
and benefits of maternal choice and planned CS. It is to be hoped that its
findings will not be taken out of context.

1. Confidential Enquiries Into Maternal Deaths. Why mothers die 1997-
1999: The
fifth report of the Confidential Enquiries into Maternal Deaths in the
United
Kingdom. No. 5. Regent's Park, London: RCOG Press; 2001.

2. Stamp G, Kruzins G, Crowther C. Perineal massage and prevention of
perineal trauma: randomised controlled trial. BMJ 2001; 322: 1277-1280.
(26 May.)

3. Fines M, Donnelly V, Behan M, O'Connell PR, O'Herlihy C. Effect of
second vaginal delivery on anorectal physiology and faecal continence: a
prospective study. Lancet 1999; 354: 983-986

Competing interests:
None declared

This study by Villar et al in this weeks BMJ concerning caesarean
childbirth tells us nothing a first year registrar could not have told us.
Women undergoing caesarean section - both emergency and elective - are
more likely to suffer morbiditiy and mortality than those that give birth
vaginally at least in part because they are more likely to have suffered
placenta praevia, placental abruption, diabetes, major medical problems,
preeclampsia and prolonged or obstructed labour - conditions not
adequately controlled for in Villar's study. Babies born by caesarean are
more likely to die or suffer harm because they will be either smaller or
larger than those delivered vaginally. They will have suffered greater
degreees of acute or chronic intrauterine compromise than those delivered
vaginally and of course emergency (either in or before labour) caesarean
is a likely - and indeed appropriate - response to evidence of fetal
compromise. Comparing women who suffer medical complications and obstetric
morbidity with those who don't does not help us.

Equipoise exists. The time has come for a large prospective long term
observational study comparing outcomes for women without absolute
indications for caesarean who plan to give birth by caesarean versus those
planning to give birth vaginally.

Competing interests:
None declared