Labour requirements in the weapons and munitions were such that the industry had to quickly train the women who were being massively recruited. In addition to learning a job, these housewives and mothers had to adapt to harsh working conditions which included carrying heavy loads.
The manufacturers had to find a solution for the new social context and some of them built nurseries and child-care centres within the factory.
Workers nicknamed “munitionnettes” made mortar shells in factories that had been converted to make weapons such as Citroën, whose workforce in 1918 was 60% female.
In the automotive industry, where labour requirements were high, the percentage of women ranged from 20% at Panhard & Levassor and Berliet to 30% at Renault.
Munitionnettes on may 1917
from wikipedia