Tusla received 182 official reports of retrospective child sexual abuse last November, according to a new report.
These cases involve people coming forward as adults to reveal they were abused when they were growing up.
The Child and Family Agency received 1,897 official reports of this kind in the first 11 months of last year.
Wexford native Joe Mooney, is an assistant professor of social work in UCD.
He says most of these cases take place in a family environment.
"In terms of coming forward, those who do so, they have to overcome significant barriers.
"They are barriers personal to themselves, overcoming shame and stigma and guilt.
"They have to overcome barriers in relation to others that may be their family.
"The hugely significant issue with sexual abuse is that it occurs within the small social cuircle of the child, more often that not within the family setting."
The number of people reporting childhood abuse is only the 'tip of the iceberg', according to a social care expert.
"In terms of the international literature of those coming forward, they are and tend to be the tip of the iceberg of those effected.
"There is no reason to suggest Ireland is any different.
"If we start to create systems and structures that facilitate, encourage and support people to come forward, we should see more people coming forward.
