13 per cent of Irish Traveller woman have seven or more children, compared with just 0.4 per cent of women in Ireland generally.
That's according to CSO figures, which show 29-thousand-573 Irish Travellers were counted in last year's Census, accounting for 0.6 per cent of the entire population.
The information is contained in a CSO report on ethnicity which has been published today.
There were 726 travellers registered as living in Donegal in Census 2011, representing 4.5 travellers per 1000 of the total population. That's slightly down on the 6.4 figure for the state.
Galway County had the highest number of Travellers - with 2-thousand-476, while Waterford County had just 152.
Among 15 to 29 year olds, 33 per cent of Travellers were married - compared to just 8.2 per cnet of the general population.
The census showed that of the 158,231 people registered in Donegal, the vast majority were Irish. 840 described themselves as African, 101 as being from another black background, and 1,307 described themselves as being Asian.1,566 people declined to answer questions on ethnicity.