Maternal Age

For the second year there has been a slight increase in the number of births in Scotland, where previously there has been a steady decline since 1976.  Within the overall fall in births in the last thirty years (from 66,000 to 52,000), there has been an increase in the proportion of babies born to women over the age of thirty. It is well established that women are having fewer children, and postponing childbirth until they are older as shown in  Table 3 . Births to mothers aged 30-34 has risen steadily, and this age group is now the most common, accounting for 30% of all maternities. Since 1976 there has also been a steady rise in the proportion of mothers aged 35+ (from 6.0% to 20%), and the number of births in this age group now exceeds those in the 20 - 24 age group. This change has obstetric implications and has contributed to the rise in caesarean sections, since it is well documented that age and obesity are correlated with increased risk of emergency caesarean section (1).

Table 4  shows the number of first births divided into deprivation quintile, which are derived from the total population rather than just the childbearing population. Although 20% of the total population are classified into each quintile, there is a slight imbalance between the least and the most deprived quintiles with a slightly higher proportion of births in quintile 5 (most deprived) compared with quintile 1 (least deprived).  However, when the data are examined by age, there are strong patterns as shown in the chart below.     

The age distribution of first births by deprivation shows a difference of approximately 13 years between the most common age for starting a family in the most deprived quintile compared to the least deprived.  In the under 20s, there are 4-5 times the proportion of births in the more deprived groups compared to the least deprived, and this pattern remains throughout the period, despite a decrease of nearly 50% in the total number of births in this age group since 1976. In the 20-24 year olds the ratio of babies born in quintile one (least deprived) to the number born in quintile five is approximately one to two, but this starts to reverse in the age group 25-29, and for the age groups 30-34 and 35-39, the ratio is two to one. Again, there is little change in this proportion over the time period. Much the same sort of pattern is seen when all births are examined rather than just first births. The data support the view that these changes in behaviour (delaying reproduction and having smaller families) are occurring in all sections of society.

Click below for related data

• All Births By Age of Mother  [181KB]
• Births (1st & All Births) by Age of Mother  [270KB]

Reference:

1. Expert Advisory Group on Caesarean Section in Scotland. May 2001.