The Pro Life Campaign has accused the Oireachtas Committee on the Eighth Amendment of acting like a "pro-choice advocate".
The Committee is reviewing the recommendations made by the Citizens' Assembly on changing Ireland's abortion laws.
The Pro Life Campaign held its national conference in Dublin today where speakers from a broad range of backgrounds gave presentations.
The Oireachtas Committee was criticised for inviting "just four pro-life speakers compared to 24 abortion advocates" to address the TDs and senators.
Sheila Quinlan of the Pro Life Campaign said: "In essence, what we are having is an Oireachtas Committee that is essentially a pro-choice advocate."
Dr Ruth Cullen said the Committee was supposed to be impartial saying its role "is to rigorously test and scrutinise any new proposals that might involve changes to the law but that simply hasn't happened".
Chair of the Oireachtas Committee, Senator Catherine Noone, responded this afternoon saying "we have to go beyond the pro-life, pro-choice polarisation of this argument".
She said it needs to be more nuanced.
Senator Noone said: "It's easy for the Pro-Life Campaign to say 24 to four [speakers]. That resonates well but the reality is that the vast majority of witnesses appearing before the Committee are pro women's health care and they're dealing with women's healthcare at the coalface."
The Pro Life Campaign believes the Committee should have invited speakers like Abby Johnson, former director of one of the largest abortion clinics in the US and David Alton, a member of the British House of Lords and expert on England's abortion law.
Both spoke at today's conference.
The Committee on the Eighth Amendment to the Constitution will begin the decision-making process this week and will publish its report on 20 December.