When it comes to attracting and retaining a significant number of women, as well as who will stick with Kajukenbo, I agree with Serene. I've been training in Kaju for only 8 years (at the same place with the same instructor) and in that time have seen many women come and go. The women who remain with Kaju and/or MMA are the ones who have a background either in very physical sports or a lot of experience with physical contact (NOT necessarily positive). In other words, pure Kajukenbo just doesn't seem like it's for everyone.
We have two active women black belts (I'm one) and one active junior woman black belt now. The other two female black belts are the daughters of one of our adult male black belts and they are blessed to have such a great dad accompany them on their Kaju journey. There are no other active adult female Kajukenbo students right now other than the three of us. There are two active (preparing for fights) MMA female students: one wrestled on a men's team at her high school in Alaska and is Army vet who served in Iraq, and the other has been in several street fights and has changed her life around. They both came in with no experience but were comfortable with the the contact. They also both work really hard.
I originally joined the Women's Kickboxing and Self Defense program to get into shape after my second kid. There were two things that closed the deal for me when I joined:
1. Sifu Chris had been instructing my son for about 6 months and I liked his coaching style (which carried down to the other instructors). I had a preconception of martial arts as being overly macho. His style of teaching was not like that. I was pretty impressed with his patience with adults and kids alike. I've heard it said many times when perusing schools, the teacher is almost as or more important than the art you choose.
2. I saw a female student take her blue belt test. She went on to become a black belt (not active now) but when I saw the self defense portion of the her test, with multiple attackers, I was so impressed I ran out after her after the test to tell her how awesome she was. She barely stopped walking to acknowledge me. In retrospect, she must have thought I was such a dork!
I had done a lot of physically challenging things before kaju: I played soccer through high school at a very competitive level, had done several marathons and triathlons, and was an accomplished mountain biker who rode mainly with men. I'd been hospitalized a couple times for some pretty bad mountain bike crashes. I joined Kajukenbo thinking "Well, how hard can this possibly be??" Ha, ha! It was hard! Hard to get hit. Hard to get kicked. Hard to be taken down over and over again. Until you get used to falling, it's hard! I admit there were many days where I thought to myself, "I just need to survive this one hour." There were also many days when Sifu Chris would say to me casually on my way out, "How you feeling?" in a seemingly rhetorical way. Looking back, he probably was actually wondering how I was feeling after getting beat up!

The classes with the most consistent female participation at Tribull are the kickboxing classes with optional sparring (or sparring separately in a Level 2 class) and CrossPit-type fitness classes that incorporate MMA or Kaju techniques, like punching, kicking, sprawls, ground-n-pound.
Based on my experience at Tribull, I think retaining female students in a pure Kajukenbo program will always be challenging. The women you retain will be the ones who are comfortable with, or even thrive on (as I feel I do), a highly physical and/or combative sport. Like mountain biking, it's the thrill of the dangerous and the scary that, once you are hooked, is hard to live without in other sports.
Thanks for taking my input into consideration. I recognize I have far fewer years of teaching and training under my belt than most on this forum, but I love Kaju and I take a special interest in women in combat sports.