Yes, girls are also doing gambling with bitcoin and I know some of them personally which are doing this fun thing to make some money for them, I think girls are more lucky than men because they are making good profit on gambling site.
I don't think so my girlfriend is really unlucky in gambling i have allowed her to play some round in bitcoin dice but she lost quite high than i have expected. However there is no any relation between luck and gender, luck is always luck and i think girls also love gambling just like boys if they know about online gambling. And with bitcoin casinos it is even easier for anyone to remain anonymous during gambling so no any gender, age or country restriction.
