60% of women in Europe have suffered gender-based or sexual violence at work, according to a study across five countries published on Saturday. 

French research group Ifop found 21% reported such attacks in the last 12 months and over 40% of those were under the age of 30. 

More than 10% of the 5,000 respondents -- nine percent in France, 15% in Spain -- said they had "forced of unwanted" sex from someone in their workplace. The study authors said that figure "highlights the grey area that may exist around consent" when it can "be extorted in a context of subordination, intimidation or manipulation."

Additionally, 9% of women said they were at least once "pressured" by a colleague to commit an "act of a sexual nature," such as sex in exchange for a job or promotion. While some 18% said they were touched inappropriately, such as a hand on the bottom, a forced hug or an unwanted kiss. 

The study was conducted in France, Germany, Italy, Britain and Spain. 

It also said sexual violence, which includes whistling, gestures, rude comments or leering, was the most common attack with 46% of women affected, especially in Germany where the figure was 56%. 

The authors of the report said "a very small minority of victims of workplace harassment manage to break the wall of silence" and speak out.

Only 13% of women who were touched inappropriately and 16% of those who were pressured into a sexual relationship said they had spoken to someone, such as a superior or trade unionist, to solve the problem internally.

The Ifop survey was conducted with an online questionnaire in April this year for the Fondation Jean Jaures think tank and the European Foundation for Progressive Studies (FEPS).