The Financial Services Union (FSU) said there is an urgent need for the adoption of workplace policies on menstrual health.
The union has released the results of a survey on the issue which shows that 91% of respondents think menstrual health affects working life.
96% said they would welcome a menstrual health support policy in the workplace.
Almost half of respondents said they are not comfortable talking about menstrual health issues in work, with 22% saying periods are joked about in the workplace.
"Historically menstruation and its effects have been ignored in the workplace despite it affecting almost 50% of the workforce," said Mandy LaCombe, Senior Industrial Relations Officer with the FSU.
"Progress has been made internationally in supporting the needs of workers who suffer from symptoms related to menstrual health, but insufficient attention has been given to the importance of menstrual health to date in both Republic of Ireland and Northern Ireland," Ms LaCombe said.
The FSU said it will use the trends gathered from its survey to influence and create guidance for future work in the area, including seeking a commitment from employers throughout the sector on the implementation of workplace policies.
