Recent rises in caesarean section rates have been substantially contributed to by a rise in the average age of first-time mothers, according to new research.
Scientists at Cambridge University analysed a large body of data in a bid to determine the association between maternal age and the outcome of labour. Alongside a major increase in the number of caesareans, they found striking changes in the age of mothers over the study period.
The proportion of women aged between 35 and 39 entering their first pregnancy increased seven-fold, while there was a 10-fold increase for women aged 40 or older.
At the same time, the caesarean rate among women having uncomplicated first births more than doubled. The researchers estimate that 38% of these additional procedures would have been avoided if the average maternal age had remained unchanged.
The team at the University's Department of Obstetrics and Gynaecology examined more than 500,000 entries collected by the Scottish Morbidity Record between 1980 and 2005.
Lead researcher Professor Gordon Smith said: "It is essential that we fully understand the effects of age on childbirth if we are to impact on rising rates of intervention in pregnancy."