There are female miners in district 12, such as Bristel, but even from what little detail Katniss gives us about the miners, the numbers are overwhelmingly male (Gale, Thom, Mr.Everdeen, Mr.Hawthorne are all male miners, whereas Bristel is the only female miner mentioned). That automatically limits the ability of Seam families to provide for themselves economically to the same level as Merchant families such as the Mellarks or Cartwrights, in which both heads of house can earn equal salary. It also ensures that in the case of a mining accident, the Seam families are certain to be beholders to the state for tesserae grain/oil to survive.
V. Arrow, The Panem Companion











