A study carried out by Mexico's National Commission to Prevent and Eradicate Violence against Women (CONAVIM) showed a correlation between the rise in femicides -- used in this case to denote any murder of a woman -- and the violence unleashed by the drug trade.

The report showed that between the years 2001 and 2010, the femicide rate grew by over 500 percent in the northeast and around 280 percent in the northwest -- corresponding to the states historically most affected by drug-related violence, including Chihuahua, Durango, Nuevo Leon, Sinaloa and Sonora.

The number of killings of women more than doubled in the three years after then-President Calderon launched his assault on criminal groups, rising from 1,119 in 2007 to 2,471 in 2010.

Between 1980 and 2010 women made up 10 percent of total homicides in Mexico. Firearms were the most common cause of death, accounting for nearly 24 percent of women's killings in 2010.

The study's coordinator, Florinda Riquer Fernandez, said that the lack of security in conflict zones made women more vulnerable, creating the conditions for gender-based violence, reported El Informador.

InSight Crime Analysis

The study's finding that the rise in violence against women has accompanied the acceleration of Mexico's drug conflict is a reminder of how organized crime can impact on social order and vulnerable populations, even if they are not involved with criminal groups.

In 2011 a women’s advocacy group reported that most Mexican female migrants to the US said they were leaving to escape violence and insecurity. Among the dangers facing them were high numbers of femicides -- in this context gender-based killings of women -- along the Mexico-US border, as well as the threat of being forced into the sex industry.

Central American countries like El Salvador, Honduras and Guatemala, also home to high levels of drug-related violence, rank among the most dangerous places in the world for women.