"Women pioneers" tends to mean women who won the West.

Strong, determined women pushing forward the frontiers. Ahead of their time, yes, but with the idea here of building a new society. I think "pioneering" could be an answer.

For example:
http://www.wes.org.uk/content/pioneering-women-engineers

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Note added at 21 mins (2014-03-05 11:43:40 GMT)
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Actually you could probably leave out the inverted commas in English.

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Note added at 1 hr (2014-03-05 12:31:54 GMT)
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I have egg on my face for not having checked and discovered that "Avanzadoras" is the official name of a campaign. There is clearly a case for leaving it in Spanish on those grounds. But if you do that I'd still be inclined to indicate what "avanzadoras" means, even though the following part makes it fairly clear. And "'Avanzadoras' women" strikes me as awkward. It should really be "'Avanzadora' women", I suppose, but even that seems a bit forced to me. Maybe "one of the 'Avanzadoras', the 'pioneering' women with whom...". In that case, I'd keep it in inverted commas to make it clear that it's a translation of "avanzadoras". And "pioneering" would still be my first choice for that. The echoes of pioneers in America and Australia are relevant, I think.