Men and women are physically different. (If that comes as a shock to anyone here, I'm sorry). In terms of wearing the kilt, women simply have larger hips than men, which means that the tapering that you traditionally see in a man's kilt would have to be very much more pronounced in a woman's.

Now, is there any reason why a woman can't wear a kilt? I suppose not, technically speaking. But it is a male garment, and that needs to be considered. The only women I can recall seeing in kilts (true kilts) are those in pipe bands, and typically the whole uniform is male -- the shirt, the jacket, the tie, the whole thing. So she's wearing it as a uniform.

Come to think of it, I can't say that I've ever seen a woman just wear a kilt as normal attire. Now there is a tendency to call any pleated, wrap around skirt a "kilt" but this is due to the superficial similarity between that style skirt and the man's garment. But in quality and construction, they simply are not kilts, but skirts.

What most women wear, who attend Scottish events and want to wear a tartan, is a "kilted skirt" which is made of a light weight tartan, has much more shallow pleats, is usually machine sewn, and closes opposite a man's kilt. It also can be worn any length, from full length to micro-mini.

Aye,
Matt