Megan was born in Drogheda, She grew up on Drogheda's Scarlet Street and was educated of course here at Our Lady's College, Greenhills and at the Institute of Technology, Carlow. She also played youth football with local Drogheda teams – Grove Rangers, Boyne Rovers and Moneymore. In 2013 Campbell began playing for Florida State Seminoles after obtaining a scholarship to Florida State University, where she majored in social science. In February 2016 Campbell became MCWFC's fourth signing of the off-season, announcing that she had signed a professional contract with the English UEFA Women's Champions League contenders Manchester City. She won a domestic treble with the club, then signed a contract extension in June 2017.She suffered an anterior cruciate ligament injury in November 2017 during a UEFA Women's Champions League match against LSK Kvinner FK and was ruled out for several months. Campbell has represented the Republic of Ireland at U-17, U-19 and senior level. At senior level, she now has more than 40 caps to her name.Commenting on signing for Liverpool FC Women, Campbell told Liverpoolfc.com: "I hope I can help the club get promoted and get back to where it belongs.