The bodies were found near a highway in the Monterrey metropolitan area.
Nineteen women have been murdered this year in Monterrey, state police said.
The northern city of Monterrey, population three million, is an industrial hub and Mexico's third most populous metropolis.
Monterrey and surrounding areas have gone from being one of the safest regions in Mexico to becoming a flashpoint in the country's continuing drug violence in recent years.
Violence in the area is blamed on turf wars between the Zetas gang and Gulf cartel.
Some 50,000 people have died in rising drug-related violence since President Felipe Calderon deployed tens of thousands of troops to take on the powerful cartels five years ago, according to media counts.