Margaret Martin, director of the domestic violence agency, said the trend emerged in countries such as the Netherlands, even though it had legalised prostitution.
She was speaking before the Oireachtas Justice Committee during a second day of hearings to discuss proposals on Irish prostitution laws.
Dr Martin said Women’s Aid supported Turn Off the Red Light, which wants Ireland to adopt the Swedish model criminalising the buyers of sex.
Women’s Aid was joined at the hearing by the Irish Feminist Network and the Sex Workers Alliance Ireland, which argues against the Swedish model.
Dr Martin told the committee prostitution was “a form of violence against women” and that criminalising buyers would send the message that “women are not commodities”.
She said legalisation had not worked, and that she was “very concerned” at the “loverboys” trend.
“Talking to our own support workers, some similar things are happening here to some extent,” she told the committee.
She said a study of 60 homeless women in Ireland last year found two thirds had experienced intimate partner violence and that 15% performed sex work to earn income.
Margaret Whitaker, who has done research among sex workers, said SWAI was “strongly opposed” to the Swedish model.
She claimed it had not worked and that Swedish police reports showed a rise in the number of men paying for sex.
Dr Whitaker said Norway, which introduced the model in 2009, was considering abandoning it, and that violence against sex workers in Oslo had risen.
She maintained organisations such as UN Aids, the UN Global Commission on HIV, the WHO, and the International Labour Organisations expressed concerns about the policy.
She said the Government should consider policies in New Zealand and Australia which had favoured regulation.
She said it was impossible to estimate what percentage of sex workers were coerced and what percentage were working voluntarily. But she said there was “no doubt” there were sex workers who operated voluntarily.