Are university dorms in poland co-ed?

Yes, nearly all university dormitories in Poland are co-educational. Maybe except for those which are run by the Church, but they are only for secondary school students (under 18). There are separate rooms for boys and for girls, but a boys' room and a girls' room might be next to each other, on the same floor. In most such places bathrooms and showers are used by both boys and girls, so it might be hard to avoid views that you might find offensive.
Most dorms are quite clean.
Good luck!

But the bathrooms and doors have doors, haven't they? And I do expect that people are not wandering naked over the corridors.
To have a female neighbour is not offensive. Some people may don't like it, but it is not offensive.

I am sorry for reacting to not my post, but as a woman, I find offensive, that somebody writes on social website, that my presence is offensive only because I am a woman.

Generally, the society here doesn't find any gender of people offensive (man or a woman) so maybe studying here is not the best place for somebody of such opinions. It will be difficult to find a seat in the classroom, that is only for men. The same with public transport, restaurants, libraries, doctors and so on. It will just very hard for such a student. Not very nice summer sin't it.

Marzenna I apologize if the reply by Kerryman hurt you in any way. I'm sure he meant "uncomfortable" instead of "offensive". Peace.
And Kerryman thank you for your reply, I'm better informed now.

Thank you for your reply. I appreciate this very much. Uncomfortable is a very good word for it and I understand that people are of different orientation and religions that makes our world so interesting.
Once again: of course "peace" and once again: I appreciate your respond. You did not have to and yet, you took the time.
I hope you will have a nice stay in Wroclaw. As Kerryman mentioned, single gender student's accommodation would be hard to find. But maybe you really could seek one in church run hostels. I am a humanist myself, but I have very good friends, that are also very involved in church matters. Should I ask them for some advice? I will be happy to do that.