For those of you who were not married in a Roman Catholic church, perhaps I should explain what Pre Cana is.
Pre Cana is what anyone wishing to be married in a Roman Catholic church has to go through. It's basically a sort of class in which the Church instructs you regarding its latest teachings on the Sacrament of Marriage and tries to give some helpful advice and warnings about what you're getting yourself into. It also helps to serve as a sort of meet-and-greet so couples-to-be can, in theory, become friendly and thereby have someone around who has something in common with them.
Pre Cana itself takes many different forms. The one Dawn and I went to was a couple of meetings of maybe ten or fifteen couples where we were talked to by a couple who had been married for some time, a pair of relative newlyweds, parents, and a priest. Altogether this was supposed to give us a rounded view of what marriage entails. It wasn't so bad and it was over quickly.
A couple of friends of ours, however, made the mistake of going on a Pre Cana retreat weekend where they were inundated with the idea of the ``traditional'' marriage where the woman stays home and cooks and cleans and the man goes out and works.
So you can see that Pre Cana experiences can vary widely. If you do have to go, good luck.