Half of Scottish babies born to mothers over 30
Mothers in Scotland are getting older, official statistics have shown.
Almost half of babies (49%) born in 2012/13 were to mothers over 30.
In the mid 1970s the proportion of older mothers was less than a fifth (19%).
The figures published by the Scottish government's Information Services Division (ISD) also reveal mothers in deprived areas are nine times more likely to give birth under the age of 20 than those in affluent parts.
The ISD report said the rise in the number of older mothers has medical consequences.
"This change has obstetric implications and is a contributory factor in the rise in caesarean sections.
"It is well documented that age is correlated with increased risk of emergency caesarean section."
ISD said elective caesarean section rates - where mothers opt for this method of giving birth for non-clinical reasons - have increased in line with the trend.
In the mid 1970s they accounted for just 4.7% of all births, but in 2012/13 that had risen to 12%
The Royal College of Midwives (RCM) said it was not surprised that mothers were becoming older.
Scottish director Gillian Smith said: "Women are waiting longer to have a child, once they have established themselves in their career.
"But because they are older when they do decide to start a family, it can take longer to become pregnant.
"And it takes longer for the body to recover - which makes having further children slightly more difficult as well."
In all, Scotland registered 58,027 births in 2012, a decrease of 3.4% compared to four years previously.
The ISD figures also highlight the way in which deprivation impacts on child birth.
In the Greater Glasgow and Clyde NHS Board area, 438 of 668 (65%) babies born to mothers under the age of 20 came from the most deprived areas.
Only 17 (2.5%) were in the most affluent parts.