Researchers say women are more likely than men to be aggressive towards their partners. A UK study that questioned over 1,100 people found women were more physically aggressive than men.
More women than men were also classed as 'relationship terrorists' who were routinely abusive.
It found that just as many women coupled controlling behaviour with serious levels of threats, intimidation and physical violence.
The study found that women demonstrated a desire to control their partners and were more likely to use physical aggression than men.
Psychologists at the University of Cumbria concluded that violence was linked to controlling behaviour such as checking up on partners.
The study focused on young students in their late teens and early 20s because statistically they were most likely to be victims of aggression.
It showed that while women tended to be more physically aggressive towards partners, men were more likely to be aggressive to same-sex "others" - including friends.