I'm a librarian who loves anime, manga, and reading a wide variety of genres.
It's taken this long to get to the first detailed mention of female Ichi-F workers. And it starts with sparklies (because the lady is so pretty). :-/
Tatsuta doesn't come right out and say it, but I'm guessing that the official reason there aren't many female Ichi-F workers is because of the effects of radiation on possible pregnancies:
"At very rare intervals, you see women in Ichi-F. But most of them were foreign media, and above a certain age."