A third of births took place outside marriage in 2010, or 25,373 in total, according to the latest Vital Statistics Report. 
It marks a 0.4 percent increase compared 2009. In that year, 25,252 children were born outside marriage, representing 33.4pc of all births in that year.
However, over the longer term, figures show that Ireland has experienced a dramatic rise in the number of children being born outside wedlock.
Since 1996, the number of children born outside marriage has gone from just over 25pc to nearly 34pc, while the actual number of children born outside marriage has gone from 37,858 to 49,802.
The rate of Irish children born outside marriage is approaching the current US rate of 40pc.
County Galway had the lowest percentage of children born outside marriage, with 24pc. Dun Laoghaire Rathdown had the lowest percentage of children born outside marriage of any urban area, with 25.6pc.
Limerick City had the highest percentage of children born outside marriage, with 55pc.
Overall, there were 75,174 children born in Ireland during 2010, down 380 or 0.5pc from 2009. While this is the first annual decrease in five years, the number of babies born in 2010 represents the second highest number of births since 1896.
The total period fertility rate (TPFR), or the average number of children per woman, was 2.06 in 2010, the same rate as in 2009, and just below replacement level. A value of 2.1 is generally taken to be the level at which a generation would replace itself in the long run, ignoring migration.
Ireland continues to have the highest fertility rate of the 27 EU member states in 2010 at 2.06 children per woman.
In 2010, there were 26,091 babies born to women aged 30 to 34, the highest number of all five year age-groups, representing over a third of all births.
The shift in the age structure of Irish fertility from a younger cohort to a somewhat older one happened in 1993.
Prior to 1993, the age-specific fertility rate was highest among women aged 25 to 29. (The age-specific fertility rate is the number of births per woman within a specific age group.) In 1993 the highest fertility rate shifted from that age group to women aged 30 to 34.
