Recently, while doing some research to prepare for a seminar, I came across a study from 2005 that provides some data indicating fighting back does not increase your chances of getting hurt. Furthermore, it does increase your chances of preventing the assault, specifically in the case of this study it was rape. The authors reviewed data from the National Crime Victimization Survey and determined that "self-protection actions", that is defending oneself, did not have a significant impact on the injury outcome of victims. The did detect a significant reduction in rape completion when self-protection actions were taken.
For the full article, click here: https://www.ncjrs.gov/pdffiles1/nij/grants/211201.pdf