Mixte frames, those with the twin lateral tubes, are generally considered to be women's but some also call them unisex bikes. Double downtube or step-through frames like this are generally considered to be women's bikes. That said, I have a Raleigh Sports ladies 23" frame waiting in the garage for the day when I can no longer swing a leg over my M23". It's just a bike and you're just a person. Ride what you want if it fits you.