According to the CSO the average age of first time mothers is 30.8, up .2 years from 2015.
Married women leave it later to have a baby, with unmarried mothers having their first child at the average age of 28.5.
Births fell by almost 4% at the end of 2016 to 16,458.
Meanwhile, latest figures show one in three mothers now has a Caesarean section – which is more than twice the rate recommended by the World Health Organisation.
Cecily Begley, Professor of Midwifery in TCD, branded the rising rate of C-sections in Ireland a ‘national disgrace’.
“We're over 30% now in Ireland and that is a national disgrace,” she said. “It increases mortality rates for women, although that is very, very rare.
“It increases morbidity, that is problems for women and for babies. There are more respiratory problems in babies after Caesarean section than for normal birth.”