Domestic violence biggest threat to women: UN
Violence against women by their live-in spouses or partners is a widespread phenomenon, both in the developed and developing world, as well as in rural and urban areas, the most comprehensive and scientific international study on the topic has confirmed.
A New York Times article also mentions the following:
The rate of abuse by partners is estimated to be around 20 percent to 25 percent in the European Union, smaller studies have found, although the problem is reported to the police in only a tiny fraction of cases.
In the United States, national surveys by the federal Centers for Disease Control and Prevention have found that about 25 percent of women said that they had been physically or sexually assaulted by a spouse, partner or date.