Could be it is luck of the draw, as I never got them and I pushed for almost 2 hours!
I think, particularly with your first, that reading some good articles about 2nd stage might be helpful. I thought that the care I'd received during my birth was fantastic, but when I think back to it now, I wish I had've known more about 2nd stage. Mine was heavily coached, I was pushing so hard I literally burst loads of little blood capillaries in my head, and it was all directed pushing, rather than just following my body's lead.
I know that this time around statistically it will be much quicker, but I still want to just trust my baby to find her way out rather than push when I don't need to, KWIM?
I don't think I've been very clear, LOL! What I'm saying is, perhaps it is unavoidable (in that, if you are going to get them, you'll get them) but perhaps learning what you can about 2nd stage, particularly working with gravity and being aware that sometimes care providers will direct you too much, might help. Know that it is normal for 2nd stage to take a while in a first birth, and you and your attendants might need to be patient, instead of pushing like mad.