Time trends in caesarean section rates and associations with perinatal and neonatal health: a population-based cohort study of 1 153 789 births in Norway

ObjectivesTo study caesarean section (CS) rates and associations with perinatal and neonatal health in Norway during 1999-2018.DesignPopulation-based cohort study.SettingMedical Birth Registry of Norway.Participants1 153 789 births and 1 174 066 newborns.MethodsCS, intrapartum, perinatal and neonatal mortality rates expressed as percentages (%) or per mille (parts per thousand) with 95% CIs.Primary and secondary outcome measuresCS rates in the Robson Ten-Group Classification System; intrapartum, perinatal and neonatal mortality rates.ResultsThe overall CS rate increased from 12.9% in 1999 to 16.7% in 2008 (p<0.001), and then reduced to 15.8% in 2018 (p<0.001). The largest reductions were observed in Robson groups 2 and 4. In Robson group 2, the planned CS rate decreased from 9.6% in 2007-2008 to 4.6% in 2017-2018, the intrapartum CS rate decreased from 26.6% in 2007-2008 to 22.3% in 2017-2018. In Robson group 4, the planned CS rate decreased from 16.1% in 2007-2008 to 7.6% in 2017-2018, and the intrapartum CS rate decreased from 7.8% in 2007-2008 to 5.2% in 2017-2018.The intrapartum fetal mortality rate decreased from 0.51 per 1000 (parts per thousand) in 1999-2000 to 0.14 parts per thousand in 2017-2018. Neonatal mortality decreased from 2.52 parts per thousand to 1.58 parts per thousand.ConclusionsCS rates in Norway increased between 1999 and 2008, followed by a significant reduction between 2008 and 2018. At the same time, fetal and neonatal mortality rates decreased. Norwegian obstetricians and midwives have contributed to maintaining a low CS rate under 17%. These findings indicate that restricting the use of CS is a safe option for perinatal health.

Automated summary

A study in Norway found that the rate of caesarean section (CS) decreased between 1999 and 2018, while fetal and neonatal mortality rates also decreased. Norwegian obstetricians and midwives played a significant role in maintaining a low CS rate below 17%, indicating that restricting the use of CS is a safe option for perinatal health.