The Seanad has been in session for fewer days since people voted to retain it last Autumn.
The Upper House of the Oireachtas met 12 times fewer compared to the period prior to the referendum.
A review of the sitting day figures by RTÉ News show the upper house met 103 times in the months leading up to the referendum on October last.
Since then, the house met 91 times, that is 12 fewer days and this breaks down as four Seanad working weeks.
Senator Catherine Noone said: "The Upper House dealt with more legislation than ever within the hours it sat."
She said the Seanad is in "the hands" of the Dáil when it comes to most legislation.
Fianna Fáil Senator Mary White said there has been a problem with legislation coming to the Seanad but senators have been busy.
She highlighted that she had two bills dealing with mandatory retirement and maternity retirement accepted by the Government.
Reforms were announced this week with a view to improving efficiency in the Upper House.
From October the Seanad will review the work of the North-South Ministerial Council and the British-Irish Council.
It will also review North-South Implementation Bodies.
Senators will also debate the European Commission's annual work programme and review reports from Oireachtas committees on EU policy proposals.