Just 13% of women who are physically or sexually assaulted by their partners in Mexico report it to an authority, according to a report the national statistics agency issued ahead of an international day of activism to combat violence against women.
Women's rights activists are set to take to the streets around the world on Friday to protest against pervasive gender violence and call for stronger action from authorities.
In Mexico, where some 20 women are killed each day, this comes as prosecutors in the state of Morelos are accused of covering up the killing of 27-year-old Ariadna Lopez, initially ruled dead as a result of alcohol intoxication.
The likelihood of women reporting physical or sexual assault was low across various circumstances, the agency, INEGI, found.
If the perpetrator was a partner, only 13.1% of women reported. For sexual and physical assault occurring at school, the ratio was just 7.8%, and it dropped to 7.1% in instances within a family, 6.5% for those at work and 4.3% in the wider community.
Meanwhile, one in two women said they had been sexually assaulted during their lives, one in five over the past year. More than a third said they had at some point been physically assaulted, including one in ten in the past year.
Not considering the incident important enough was the most common reason for not reporting it. Women also mentioned not knowing how to, being afraid of repercussions, being blamed or not believed, and feeling ashamed.
When they did report it, they were more likely to go to a public ministry than the police, though if it happened at work they were more likely to seek out a trade union or manager. If they were students, they would more likely go to a school authority.
The survey, which covered women and girls aged 15 and older, recorded highest rates of violence among those aged up to their mid-twenties.