Classification of Primary Caesarean Sections in Labor and its Usefulness for Analysis of Slovenian Perinatal Data

To determine the usefulness of a novel classification of indications for caesarean section (CS) in labour in recognizing differences in clinical practice in different maternity units.

Data from the National Perinatal Information System (NPIS) for 2013 and 2014 were used to classify indications for CS in nulliparous women with spontaneous onset of labour at ≥37 weeks with single cephalic foetuses within 14 Slovenian maternity units into foetal distress and different sub-groups of dystocia according to use and dosage of oxytocin. Chi-square test was used for statistical comparison between units (P≤0.05 significant).

There were 13,572 deliveries and 1,567 (12.0%) CS in nulliparous patients with spontaneous onset of labour at ≥37 weeks with single cephalic foetuses in Slovenia during the study period. Rates of CS in this group of women differed significantly among different maternity units (from 4.1% to 20.9%; P<0.001) suggesting significant differences in clinical practice. The most common indication for CS was cephalopelvic disproportion, which was diagnosed with different frequency in different units (from 11.2% to 45.9%; odds ratio 6.72; 95% confidence interval 3.10- 14.71; P<0.001).

It is possible to use NPIS data to retrospectively classify indications for CS. Such classification reveals significant differences among maternity units and could allow for a meaningful analysis of CS rates in different hospitals leading to evidence-based initiatives to decrease the incidence of primary CS.