Intervention Rates in Spontaneous Term Labour in Low Risk Nulliparous Women
Authors: Cary Andrew J. 
Published: February 2008

EDITORIAL COMMENT: The author has shown that private patients have significantly increased rates of forceps delivery and Caesarean section but has not told us why! Although it is undeniable that many women who are delivered by Caesarean section would have preferred a spontaneous vaginal delivery, in the editor's experience very few are resentful that Caesarean section was deemed necessary and performed — perhaps because the reason for the operation was explained to patient and partner. Patients' reactions to Caesarean section are discussed in future pregnancies when requirements for trial of scar are considered and explained. Whilst many women agree to a trial of scar, there are also many who prefer an elective Caesarean section and are keen to avoid the possibility of another labour plus another Caesarean, the odds for this second double dose being 20–40%. We will be glad to publish in this journal just what is the ‘wide ranging medical and psychological impact’ of forceps delivery and Caesarean section in a large consecutive series of properly counselled patients — what proportion of patients having forceps or Caesarean section are unhappy clients?

As intervention rates have risen, the difference between public and private patients has, in most series, been maintained. It is usually assumed that private patients have excessive intervention, yet it would seem more logical to expect better treatment when the patient seeks out a particular specialist who manages her pregnancy. There must clearly be a different philosophy between how consultants manage private patients and how nonprivate patients are managed by midwife, medical student, trainee specialist and consultant only when necessary. Perhaps the consultant, being trained to provide all the delivery options, is more likely to perform forceps delivery or Caesarean section at the appropriate time. Many Caesarean sections are done for humanitarian reasons for a relatively difficult labour with relative cephalopelvic disproportion with or without a degree of fetal distress. Higher rates of forceps delivery in private practice are easily understood if the accoucheur has as her/his aim that there is no value in delay when the head is safely accessible — 10–15% of stillborn infants die just before birth without there having been previous evidence of distress; neonatal deaths also occur due to unsuspected intrauterine hypoxia. Episiotomy ± forceps delivery when the head is low could reduce the number of perinatal deaths and minimize the risks of hypoxia, so improving the intellectual quality of survival (1). Although this philosophy is opposed by those who favour natural birth with a minimum of interference it seems likely that private patients receive better care and better counselling. In spite of the above remarks, it is also undeniable that different specialists practising in the same community, have very different Caesarean section rates, the difference unlikely to be fully accounted for by a higher proportion of high risk patients.

1. Beischer NA, Mackay EV. Obstetrics and the Newborn, 2nd Ed. Saunders 1986; p 399.

RESPONSE TO EDITORIAL COMMENT  Thank you for the opportunity to reply to the Editorial Comment. The study is an analysis of the incidence of intervention rates and did not address the issue of causation of the differences identified. We agree that the reasons for the marked difference in intervention rates need to be sought in order to justify them.

The study population of low risk nulliparas in spontaneous term labour was chosen to eliminate obvious confounding variables such as breech presentation, induction of labour, medical disorders (diabetes, pregnancy‐induced hypertension), past obstetric history etc. which by their very nature have a profound effect on mode of delivery and management of labour. Thus we believe that the differences identified are not based on purely medical grounds. The explanation, therefore, could well relate to differences in attitudes of the practitioners and the patients (Public and Private) to the options of operative and instrumental delivery.

As the perinatal outcomes are similar for the 2 groups the onus rests with us, as obstetricians, to justify these markedly higher intervention rates (with their obvious association of higher maternal morbidity) perhaps by using other outcome indices. If, however, no benefit can be demonstrated, the onus rests equally with us to take active steps to correct the imbalance.

We also agree that further studies of low risk obstetrics are required to confirm and explore the differences identified in this study.

Andrew J. Cary, MBBS.

James F. King, FRCOG, FRACOG.

Edwin J. Esler, FRCOG, FRACOG.

Summary: This study analyses retrospectively the outcome of labour in 3,058 consecutive low risk nulliparous women in spontaneous labour at term in public and private care at the Mater Mothers' Hospital, Brisbane, Queensland. Differing rates of spontaneous, instrumental or Caesarean deliveries were found between the public and private cohorts (spontaneous vaginal delivery 73.7% public, 48.6% private; instrumental 17.9% public, 35.4% private; Caesarean section 8.4% public, 16% private.) These differences were all highly statistically significant (p<.001). Other statistically significant differences were evident in durations of labour and second stage of labour. Demographically the 2 groups were dissimilar, illustrated by differences in age distribution. Correcting for age difference failed to account for the differences in frequency of dilivery methods between the private and public groups.