Communists stricto sensu were amongst the first feminists, but very early you had a divide between "bourgeois feminists" and the Marxist ones.
For instance 8 March, International Women's Day comes from the German Communist Clara Zetkins.
Alexandra Kollontai is also a famous Communist defending women's rights.
And in general women are very influential in the early Communist movements compared to their influence in other political movement. Think of Rosa Luxemburg for instance, a major theorist of Communism, or the role of women such as Louise Michel in the Commune de Paris (that's not fully Communist yet, but it was one of Marx's main sources of inspiration). Moreover, even in the pre-Marxist theorists of Utopian Socialism (Charles Fourier for instance) you find some thinking on women's lives which is very much ahead of its time.
Now, after Stalin's counter-revolution, the situation in USSR and other so-called Communist countries is more ambiguous. There has been a big leap backwards, and society is much more conservative than what it was during the revolution. But on many sides, even after this large regress, the situation of women in the East is still much better than in the West: they can vote, most of them work, they have access to abortion, and so on. And the governments (as well as guerillas, in particular in Vietnam) use the liberation of women a lot in their propaganda. For the result look at Angela Merkel for instance: a powerful women with a physics PhD leading one of the most powerful countries in the world: she's a child of East Germany, almost a cliché.