The Migrant Rights Centre in Ireland has said there are hundreds of cases of slavery here similar to that of the three women in London.
The women, one of whom is Irish, were rescued from a house in Lambeth last month.
A couple, aged in their 60s, were arrested but have been released on bail.
Director of the Migrant Rights Centre in Ireland, Siobhan O'Donoghue, said the recession has caused an increase in the number of cases.
She said: "It is going on in Ireland, we've had over the last six years 200 cases of forced labour that we have identified, and we're just one organisation.
"Especially in a climate of austerity and recession where people end up in the most destitute situations and really have very little choice."