Well to put it in perspective, Venus Williams is 145 lbs, making her a 125 or 135 lber. And Serena is 165 lbs, putting her in range of dehydrating to the 145 lb weight class. Women can't build muscle like men can. So, there's not a wide range of weight; it's pretty much dictated by height. A 6' woman is fighting at 135 or 145. That's equivalent to a 6'5 guy. You're not getting women in shape that can't make 145 until you start getting huge girls like 6'2"+, and that's like being a 6'8" dude. Really, really rare; most HWs are muscled up shorter guys and women can't do that. There's just not any 6'2"+ girls doing MMA. You'd have a division with like 1 athlete.