Career
She was in Ireland's 2014 Women's Rugby World Cup squad. She scored a try in Ireland's defeat of the Black Ferns at the 2014 World Cup. O'Brien studied Physical therapy at Queen Margaret University.
She runs her own clinic, the North Cork Physiotherapy & Acupuncture Clinic, in Mallow, County Cork. She was awarded the Evening Echo Ladies Sportstar of the Month for August 2014.
