I had one, organised by my sister for me and it was a great catch up with heaps of girls that I hadnt see for a long time. As far as it being selfish, I guess it depends on the person who is having it, but I know that I received gifts that as Ruth mentioned would have cost hardly anything and others that were extravagant (from family!) and I couldnt care less, it was more about celebrating the baby to come and having a catch up.
I dont think they are out of fashion and think they can be done tactfully. Enjoy!