'Too posh to push' claim rejected in Caesarean study
The ‘’too posh to push’’ charge levelled at some mothers is not responsible for the high variation in rates of Caesarean births, according to a study published today.
Instead, inconsistencies of care are responsible for the large variation in rates of emergency Caesarean section across England, claims the research in the British Medical Journal (BMJ).
Since the 1970s, many developed countries have experienced a substantial growth in Caesarean section rates - In England, the rate has increased from 9% in 1980 to almost 25% in 2008-09.
But the results of the study do not support the view that low-risk women are requesting elective Caesareans for non-medical reasons.
Recent figures also show that caesarean rates vary substantially between English NHS trusts, with higher rates in the south of England compared to the north. But these figures did not take account of differences in patient populations.
Researchers based at the Royal College of Obstetricians and Gynaecologists examined whether the variation could be explained by maternal characteristics or clinical risk factors.
Using routinely collected hospital data, they analysed births among women aged between 15 and 44 years at 146 English NHS trusts during 2008.
A mathematical model was then used to estimate the likelihood of women having a Caesarean section based on patient characteristics (age, ethnicity, number of previous pregnancies, social and economic deprivation) and clinical risk factors (previous Caesarean, breech presentation, fetal distress).
Among 620,604 births, almost one in four (24%) were delivered by Caesarean section. A high proportion of women underwent a Caesarean section if they had previously had a caesarean (71%), a breech baby (90%), or serious medical complications (85%). The likelihood of a Caesarean was also higher in older women.
After adjusting for maternal characteristics and clinical risk factors, Caesarean rates still varied considerably, from 14.9% to 32.1%. However, adjustment removed the north-south divide.
Most of this variation was associated with rates of emergency Caesarean section, which probably reflects the lack of a precise definition for fetal distress or dystocia (an abnormal or difficult labour) - both common reasons for an emergency caesarean - as well as differences in practices among professionals, say the authors. These findings also challenge the view that low-risk women are requesting elective caesareans.
Researchers now suggest that comparing unadjusted Caesarean section rates should be avoided and have called on NHS trusts to examine the reasons for this variation in their regions, and how the consistency of care for pregnant women can be improved.
“This research indicates, at a minimum, the need for more informed surveillance of Caesarean sections at a hospital, regional, and national level,” say Marian Knight from the University of Oxford and Elizabeth Sullivan from the University of New South Wales, in an accompanying editorial.
They call for “a more detailed examination of variations in caesarean delivery practice and the generation of the high quality evidence needed to inform practice guidelines’’.