dd1 - 4 hours (compound presentation & asynclitic - that just SUCKED!)
dd2 - no pushing by me required - she came out all on her own (so like, a contraction for her head and a contraction about 2 min later for her body)
ds1 - again, no pushing required by me - I said, "I'm sure I'm pushing" and out he came!
ds2 - same thing - my body did the work. Not sure if he was born in one or two contractions though. May have been one for his head & one for his body, but not more than that.
Fwiw, all my births have been very fast. The first was just short of 10 hours (so 6 before that long pushing stage most likely due to a non-optimally positioned baby) but then they went 90 min., 41 min., and 2.5 hours after his brother (twins). So I guess I just go fast! All were natural, at home.