The number of parents contacting the Children At Risk in Ireland (CARI) helpline with concerns about their young child's sexualised behaviour increased by 57% last year.
CARI's annual report for 2011 shows that 212 calls were made regarding the sexualisation of children under the age of 12 - up from 122 the previous year.
Overall, there was a 12% increase in calls to CARI in 2011.
National clinical director with CARI Niall Muldoon said that the internet and smartphones provide children with easy access to pornography.
"There's a change in the sexual norms for children and the availability of sexualised images and behaviours that they can see without necessarily understanding, and this is just a very clear manifestation of that," he said.
"The 57% increase in one year is huge."