In 2005 at the age of 14, Franco won the 10,000 meter race walk at the Pan American Junior Athletics Championships in Windsor, Canada, setting a new record in the event.

The following year, aged 15, she won the 4,000 m race walk in the Central American and Caribbean Junior Championships, under-17 category, again setting a competition record.

In March 2011, Franco won the Pan American Race Walking Cup, her first major title, and in August 2011 at the World Championships she finished in 19th place in the 20 km event, being the top ranked woman from the Americas and setting high expectations for the Pan American Games competition later that year.

On 23 October 2011, at the age of 20, she won the 20 km race walk at the Pan American Games in Guadalajara, Mexico, breaking the Pan American Games women's record in the process and finishing the event 59 seconds ahead of her compatriot Mirna Ortíz, who finished second.

[4] At the 2012 Memorial Mario Albisetti, Franco set a 20 km walk best of 1:30:57 hours, taking fourth place overall.