There certainly should be. Women typically have a narrower heel and taller arch than a man. So a boot that is billed as suitable for women should be built on a last (the mold used to form the boot) that reflects these characteristics, rather than simply taking a mens boot and down-sizing it.
La Sportiva Glacier Boot
And the La Sportiva Glacier ($250) is indeed built on a womens last and should be a good-fitting boot. Overall its an excellent piece of footwear for heavy backpacking and light glacier mountaineering, with one-piece waterproof-leather uppers, a half-length steel shank for support, and tough toe rands for protection.
In the case of the Glacier, the womens model also comes in a pretty shade of blue, so that may be seen as a plus. Or not.
Another excellent boot to consider is the Scarpa Charmoz GTX Lady ($260), which is similar in purpose to the Glacier, with a little more modern design. The Charmoz has a synthetic upper thats waterproof, as well as a Gore-Tex liner. Its lighter than the Glaciers, toonearly a pound lighter per pair. And its built on a womens last for good fit.
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