Would be interesting to know how many of them had their mums there when they were giving birth - particularly if they invited their mums or just had the mums invite themselves...
No way would I want my mum at a birth - and then when ds1 was born, dh was very ill, dmum and dsis volunteered to come and be my birth partner. dh was able to be there for short periods and daunt also stepped in, in a personal capacity rather than as a medic.
I remember being on the bed in the birthing suite with my mum and sis sitting at the end of the bed and just feeling that I knew they were there because they loved me and wanted to help - but I felt like a monkey in the zoo being watched. It was horrible. Nothing really happened.
Thank goodness they went off and daunt turned up for another turn with dh - and I think it's no coincidence that the midwives went from discussing all sorts of things to speed things up as they thought nothing was happening (I'd been induced so they were expecting things to happen and I was way behind the curve of what should have happened) to ds being born very quickly (to the point that they were telling me that I'd got hours and hours left and then being surprised when I was pushing and ds1 popped out a few minutes later).
Needless to say when ds2 was born, I'd moved and when dmum volunteered to help, rapidly co-opted her to look after ds1 and booked a doula to help in the delivery room... she was wonderful and ds2 popped out very quickly, and no stress for dh who was still ill enough for me to worry about, hence getting extra support but done professionally!
I have 2 ds so don't ever expect to be in a delivery room again... If I had a dil who I was close to and she asked I would consider it - but only if she was really really sure and knew what she was letting herself in for, and who would be happy to tell me to go if she realised she didn't want me there!