Mums labours were 18 hours (me), 6 hours (prem sister), 5 hours, 3 hours, 2 hours and 6 hours (induction) My first was 11 hours and then I had cs for the rest.
I don't think there is any link between generations. Same in regards to going into labour. I.e my mum was 3 weeks early with all ofher pregnancies so I am going to go into labour early as well. Different woman, different body IYKWIM.
My mum always informed me I come from a long line of "birthers" lol. She had great labours and I had a great labour. I think if you have a similar physiology to your mum, there is a good chance you will birth the same. From what I've seen and heard anyways
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