Introduction
The increasing CS rate is a subject of debate within perinatal care.1, 2 In order to monitor CS rates at national and institutional levels WHO, FIGO and EBCOG in addition to many national professional societies have endorsed the Ten-Group-Classification System (TGCS) as the most appropriate tool for clinical audit.3-6 The TGCS classifies all women into clinically relevant groups each having a specific CS rate. It serves as the initial structure within which epidemiological variables, processes, perinatal events and outcomes can be analysed. The philosophy of the TGCS is based on ‘an intention to treat’.4, 7, 8However although the TGCS tells you which women have a CS it does not tell you why.
Internationally there is no consensus on classification of indications for CS and none fulfill the criteria of simplicity, usefulness, reproducibility and robustness.9 Indications for pre-labour CS need to be considered differently from those performed after spontaneous or induced labour and therefore deserve a separate classification.10 Most indications used are very detailed, often subjective and multiple and frequently overlap. This may result in long lists of possible indications which has limited use on a day-to-day basis to understand, change and improve care. Using a high level classification system of CS initially prior to more detailed and subjective indications both in prelabour CS and after spontaneous or induced labour may provide the solution.
In 2014-15 a national quality improvement initiative, focusing on the appropriate and safe use of oxytocin in labour took place at delivery units in Norway. During this project, Norwegian maternity health caregivers became aware of a new high level intrapartum CS classification system (ICSCS) (Fig.1), incorporating information on the fetal condition, the dynamic progress of labour, the use or not of oxytocin to accelerate or induce labour and the frequency of contractions. 10-12 This new ICSCS gives a unique insight into the study and management of dystocia and the use of oxytocin. The authors emphasize that the classification is designed to be used irrespective of how you manage labour and must not be misinterpreted as clinical guidance on how to manage labour. Specifically the division of dystocic labours into those with efficient (progress ≥1 cm/h) or inefficient (progress <1 cm/h) uterine action is not an imperative for clinical management, but a pragmatic cut-off to differentiate between the different dynamics of labour.
This classification has been used in The National Maternity Hospital, Dublin since 2005 13 but had never been formally tested outside that hospital. Following national discussion and agreement, a prospective study was initiated in Norway to test the practicalities and possible benefits of using this new ICSCS in spontaneous and induced labour.