Yes I second that maryeliza, using the word only gives credence to a term that is wholly superfluous and diminishes us. I do believe that the onus should be on the infinitesimal minority to redefine themselves rather than the overwhelming majority where nothing will have changed as far as what sex we are since birth.
Whilst I appreciate language is evolving all the time, my perception is that most women will have never have come across such a word. A friend of mine who was asked to complete some sort of questionnaire at her place of work, was given multiple choices of how she wished to describe herself, "cis" being one of them, she wrote "no idea what a cis woman is so couldn't say one way or the other." That I imagine would be the response of the wider population. Those women who are familiar with the term, through sites like MN, I think you will find can't stand it.
Julia Hartley-Brewer told a man on air, that she would ask him to leave her studio when he used it. It might be a tiny word but adopting it has massive ramifications. We should collectively resist accepting it's use.