The group, La Maison Du Vélo (House of Cycling), has organised a debate for Thursday evening to discuss the issue, reports regional newspaper La Dépeche du Midi.
Dangers associated with skirts include those that are too short hindering the movement of the legs and those that are too long taking on a life of their own.
"A skirt that's too long can get caught in the wheels and cause an accident," said one cyclist, reported on the newspaper's website.
Special bicycle attachments are available that can stop the skirt getting caught in the wheels.
Another cyclist complained that short skirts can attract unwanted attention from men.
"I don't know if cycling in a skirt is dangerous, but I will say it can attract unwanted remarks and wolf-whistles," said Margot, another cyclist.
Suzannha Etienne, who specialises in workplace issues and will speak in the debate, thinks that too much fuss about what to wear while cycling is wrong and is holding back women from taking to two wheels.
"The question of clothing is one of the biggest issues holding back women in companies who want to cycle," she said.
"People think that cycling requires special sporting prowess and that a specific outfit is necessary. But that's not true."
One cyclist thought the real danger of cycling in skirts was for men, not the women on bikes.
"Perhaps men risk having an accident if they're looking at women while driving," she said.