I ve been ridin since I was knee high to a grasshopper(20+yrs)and knock on wood, i`ve layed down one of my first dirtbikes not so hard and set one of my first streetbikes down ever so gently on some gravel...i`ve been lucky I guess and hope it continues to be good to go for me and hopefully everyone here continues to keep the rubber side down as well!
I would think that it would be more a matter of the level of experience of the rider, which would determine if he or she dumped the bike more or less, rather than their gender.
As the "Ride like a Pro" video series points out, one does not need brute strength in order to ride a heavy cruiser bike like a Harley, or whatever make you choose. It is more a matter of cordination, balance, skill, and tons of practice than anything. If those 100-120 lb. former stewardesses can ride and balance a Harley and make it look easy as pie, than anyone should be able to.
There are far fewer women riders than man, so logic would say more men drop bikes than women. Drop or Crash? Everyone will eventually do both; so it is a function of experience and time. Everybody puts their foot down in a hole lower than the tipping point or slips on that slick spot...
Even the most experienced riders drop bikes once in a while. I didn't have my first crash until I'd been up for almost 20 years. I've certainly dropped a bike or two or 6 in 28 years of riding the highways and biways. A lot of the new motorcycle culture is all about "never been dropped." Most likely, it hasn't ever been ridden.
80% of the experienced bikers I know don't even believe a bike is theirs until they put a scratch on it.