Just a quick anecdote: anyone who thinks a woman cannot defend herself in a unarmed contest/fight has obviously never been a newbie at judo.

Incidentally, for any women seeking personal defense techniques I would highly recommend a grappling art such as Judo, Wrestling or Brazilian ju-jitsu. They are designed for people to overcome superior strength and I've read more than my share of news stories about 70+year old grandmothers subduing young vandals for 20 minutes using judo

Of course, I also recommend learning things which can provide assymetrical advantage to you such as weapons training. Always a plus to know how to use a knife or gun. But yeah. Bottom line is women are stronger than you think guys, especially if they've been doing judo for 6 months and it's your first day.