The number of mothers in Australia increased by 18% between 2002 and 2011 and first-time mums are also older.
In 2011, 297,126 women gave birth to 301,810 babies with the average age of mothers increasing from 29.4 years in 2002 to 30 years in 2011.
The data is contained in a report by the AIHW entitled Australia’s Mothers and Babies 2011.
Age of first-time mums
“The average age of women having their first baby has increased steadily from 27.6 years in 2002 to 28.3 years in 2011, and the number of teenage mums has declined,” according to Professor Elizabeth Sullivan of the Australian Institute of Health and Welfare (AIHW).
Of all first-time mums, 14.2% were 35 years or older compared with 11.2% in 2002.
Increase in caesarean section
The caesarean section rate has shown an upward trend in the 10 years to 2011, rising from 27% to a peak of just over 32% between 2002 and 2011.
“Caesarean section rates increased with advancing maternal age,” Professor Sullivan said.
“In 2011, caesarean section rates ranged from 18% for teenage mothers to 49% for mothers aged 40 and over.”
Repeat caesarean sections occurred for 84% of mothers with a history of caesarean section.
Indigenous mothers were significantly less likely to have caesarean section than non-Indigenous mothers. Professor Sullivan said this could be because Indigenous mothers were younger than non-Indigenous mothers.
Professor Sullivan said the report also shows that the number of teenage mums declined from 4.9% in 2002 to 3.7% in 2011, but teenage births have a range of increased health risks compared with other births.
“Teenage mothers are more likely to have smoked during pregnancy,” said AIHW spokesperson, Professor Elizabeth Sullivan.
“Of all teenage mothers, almost 36% reported smoking during pregnancy, compared with 13% of all mothers. Teenage mothers also have higher proportions of low birth weight babies compared with women in other age groups and the highest fetal, neonatal and perinatal death rates.”
Indigenous mothers were more likely to be teenagers (19%) than non-Indigenous mothers (3%).
In 2011, just over 6% of liveborn babies were of low birthweight (less than 2,500 grams). Among mothers who smoked during pregnancy the proportion of low birthweight babies was nearly double (11%).