Martens won the Norwegian Junior Championship [no] at the age of 12 and was named the 2003 Golfer of the Year in Norway.

[1] Martens was a student at NTG Bærum [no] between 2002 and 2005,[2] and attended Louisiana State University between 2005 and 2009, where she obtained a bachelor's degree in psychology.

Playing four years on the LSU Lady Tigers team she had a career average of 76.6 for 109 total rounds.

In 2011, she played a limited Ladies European Tour schedule before joining the LET full time in 2012, where her best finish was a tie for 9th at the ISPS Handa Ladies British Masters at Buckinghamshire Golf Club, 3 strokes behind winner Lydia Hall.

In 2013, she suffered a shoulder injury and played mainly on the LET Access Series, where she tied for 3rd at the Mineks Ladies Classic in Turkey and lost a playoff at the Swedish PGA Championship held at Kristianstad Golf Club.