In 2007, she captained the England A side in their second outing of the European Championships in Madrid, Spain.[1] In 2009, the Black Ferns toured England in a two-test series, she featured in the match that saw her side defeat the World Champions 10–3.[2]
Essex was a member of the England side that were Six Nations champions and Grand Slam winners ahead of the World Cup.[3] She represented England at the 2010 Women's Rugby World Cup.[4] In 2011, She was also in the English side that won their sixth Six Nations title and crowned Grand Slam winners again.[5]
Essex earned her 50th cap in the 2014 Women's Six Nations match against Ireland.[6] She was subsequently named in the squad that won the 2014 Rugby World Cup.[7] Later that year, she announced her retirement from the English team but would still play for Richmond.[7] She works as the head of an ASD center at Strand on the Green school in Chiswick.[8]
In 2015, she became an RFU Disciplinary Panel member.[9] She returned to the pitch in November 2017 when she was invited to play for the inaugural Women's Barbarians team against Munster, her side won 19–0.[9][10]